From e1e8d058a33f7566f9c565d04b0d8b56f9645c35 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Wed, 25 Apr 2018 09:28:54 +0200 Subject: add vendor --- vendor/golang.org/x/image/vp8/decode.go | 403 +++++++++++++++++++ vendor/golang.org/x/image/vp8/filter.go | 273 +++++++++++++ vendor/golang.org/x/image/vp8/idct.go | 98 +++++ vendor/golang.org/x/image/vp8/partition.go | 129 +++++++ vendor/golang.org/x/image/vp8/pred.go | 201 ++++++++++ vendor/golang.org/x/image/vp8/predfunc.go | 553 +++++++++++++++++++++++++++ vendor/golang.org/x/image/vp8/quant.go | 98 +++++ vendor/golang.org/x/image/vp8/reconstruct.go | 442 +++++++++++++++++++++ vendor/golang.org/x/image/vp8/token.go | 381 ++++++++++++++++++ 9 files changed, 2578 insertions(+) create mode 100644 vendor/golang.org/x/image/vp8/decode.go create mode 100644 vendor/golang.org/x/image/vp8/filter.go create mode 100644 vendor/golang.org/x/image/vp8/idct.go create mode 100644 vendor/golang.org/x/image/vp8/partition.go create mode 100644 vendor/golang.org/x/image/vp8/pred.go create mode 100644 vendor/golang.org/x/image/vp8/predfunc.go create mode 100644 vendor/golang.org/x/image/vp8/quant.go create mode 100644 vendor/golang.org/x/image/vp8/reconstruct.go create mode 100644 vendor/golang.org/x/image/vp8/token.go (limited to 'vendor/golang.org/x/image/vp8') diff --git a/vendor/golang.org/x/image/vp8/decode.go b/vendor/golang.org/x/image/vp8/decode.go new file mode 100644 index 0000000..1bb5028 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/decode.go @@ -0,0 +1,403 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package vp8 implements a decoder for the VP8 lossy image format. +// +// The VP8 specification is RFC 6386. +package vp8 // import "golang.org/x/image/vp8" + +// This file implements the top-level decoding algorithm. + +import ( + "errors" + "image" + "io" +) + +// limitReader wraps an io.Reader to read at most n bytes from it. +type limitReader struct { + r io.Reader + n int +} + +// ReadFull reads exactly len(p) bytes into p. +func (r *limitReader) ReadFull(p []byte) error { + if len(p) > r.n { + return io.ErrUnexpectedEOF + } + n, err := io.ReadFull(r.r, p) + r.n -= n + return err +} + +// FrameHeader is a frame header, as specified in section 9.1. +type FrameHeader struct { + KeyFrame bool + VersionNumber uint8 + ShowFrame bool + FirstPartitionLen uint32 + Width int + Height int + XScale uint8 + YScale uint8 +} + +const ( + nSegment = 4 + nSegmentProb = 3 +) + +// segmentHeader holds segment-related header information. +type segmentHeader struct { + useSegment bool + updateMap bool + relativeDelta bool + quantizer [nSegment]int8 + filterStrength [nSegment]int8 + prob [nSegmentProb]uint8 +} + +const ( + nRefLFDelta = 4 + nModeLFDelta = 4 +) + +// filterHeader holds filter-related header information. +type filterHeader struct { + simple bool + level int8 + sharpness uint8 + useLFDelta bool + refLFDelta [nRefLFDelta]int8 + modeLFDelta [nModeLFDelta]int8 + perSegmentLevel [nSegment]int8 +} + +// mb is the per-macroblock decode state. A decoder maintains mbw+1 of these +// as it is decoding macroblocks left-to-right and top-to-bottom: mbw for the +// macroblocks in the row above, and one for the macroblock to the left. +type mb struct { + // pred is the predictor mode for the 4 bottom or right 4x4 luma regions. + pred [4]uint8 + // nzMask is a mask of 8 bits: 4 for the bottom or right 4x4 luma regions, + // and 2 + 2 for the bottom or right 4x4 chroma regions. A 1 bit indicates + // that that region has non-zero coefficients. + nzMask uint8 + // nzY16 is a 0/1 value that is 1 if the macroblock used Y16 prediction and + // had non-zero coefficients. + nzY16 uint8 +} + +// Decoder decodes VP8 bitstreams into frames. Decoding one frame consists of +// calling Init, DecodeFrameHeader and then DecodeFrame in that order. +// A Decoder can be re-used to decode multiple frames. +type Decoder struct { + // r is the input bitsream. + r limitReader + // scratch is a scratch buffer. + scratch [8]byte + // img is the YCbCr image to decode into. + img *image.YCbCr + // mbw and mbh are the number of 16x16 macroblocks wide and high the image is. + mbw, mbh int + // frameHeader is the frame header. When decoding multiple frames, + // frames that aren't key frames will inherit the Width, Height, + // XScale and YScale of the most recent key frame. + frameHeader FrameHeader + // Other headers. + segmentHeader segmentHeader + filterHeader filterHeader + // The image data is divided into a number of independent partitions. + // There is 1 "first partition" and between 1 and 8 "other partitions" + // for coefficient data. + fp partition + op [8]partition + nOP int + // Quantization factors. + quant [nSegment]quant + // DCT/WHT coefficient decoding probabilities. + tokenProb [nPlane][nBand][nContext][nProb]uint8 + useSkipProb bool + skipProb uint8 + // Loop filter parameters. + filterParams [nSegment][2]filterParam + perMBFilterParams []filterParam + + // The eight fields below relate to the current macroblock being decoded. + // + // Segment-based adjustments. + segment int + // Per-macroblock state for the macroblock immediately left of and those + // macroblocks immediately above the current macroblock. + leftMB mb + upMB []mb + // Bitmasks for which 4x4 regions of coeff contain non-zero coefficients. + nzDCMask, nzACMask uint32 + // Predictor modes. + usePredY16 bool // The libwebp C code calls this !is_i4x4_. + predY16 uint8 + predC8 uint8 + predY4 [4][4]uint8 + + // The two fields below form a workspace for reconstructing a macroblock. + // Their specific sizes are documented in reconstruct.go. + coeff [1*16*16 + 2*8*8 + 1*4*4]int16 + ybr [1 + 16 + 1 + 8][32]uint8 +} + +// NewDecoder returns a new Decoder. +func NewDecoder() *Decoder { + return &Decoder{} +} + +// Init initializes the decoder to read at most n bytes from r. +func (d *Decoder) Init(r io.Reader, n int) { + d.r = limitReader{r, n} +} + +// DecodeFrameHeader decodes the frame header. +func (d *Decoder) DecodeFrameHeader() (fh FrameHeader, err error) { + // All frame headers are at least 3 bytes long. + b := d.scratch[:3] + if err = d.r.ReadFull(b); err != nil { + return + } + d.frameHeader.KeyFrame = (b[0] & 1) == 0 + d.frameHeader.VersionNumber = (b[0] >> 1) & 7 + d.frameHeader.ShowFrame = (b[0]>>4)&1 == 1 + d.frameHeader.FirstPartitionLen = uint32(b[0])>>5 | uint32(b[1])<<3 | uint32(b[2])<<11 + if !d.frameHeader.KeyFrame { + return d.frameHeader, nil + } + // Frame headers for key frames are an additional 7 bytes long. + b = d.scratch[:7] + if err = d.r.ReadFull(b); err != nil { + return + } + // Check the magic sync code. + if b[0] != 0x9d || b[1] != 0x01 || b[2] != 0x2a { + err = errors.New("vp8: invalid format") + return + } + d.frameHeader.Width = int(b[4]&0x3f)<<8 | int(b[3]) + d.frameHeader.Height = int(b[6]&0x3f)<<8 | int(b[5]) + d.frameHeader.XScale = b[4] >> 6 + d.frameHeader.YScale = b[6] >> 6 + d.mbw = (d.frameHeader.Width + 0x0f) >> 4 + d.mbh = (d.frameHeader.Height + 0x0f) >> 4 + d.segmentHeader = segmentHeader{ + prob: [3]uint8{0xff, 0xff, 0xff}, + } + d.tokenProb = defaultTokenProb + d.segment = 0 + return d.frameHeader, nil +} + +// ensureImg ensures that d.img is large enough to hold the decoded frame. +func (d *Decoder) ensureImg() { + if d.img != nil { + p0, p1 := d.img.Rect.Min, d.img.Rect.Max + if p0.X == 0 && p0.Y == 0 && p1.X >= 16*d.mbw && p1.Y >= 16*d.mbh { + return + } + } + m := image.NewYCbCr(image.Rect(0, 0, 16*d.mbw, 16*d.mbh), image.YCbCrSubsampleRatio420) + d.img = m.SubImage(image.Rect(0, 0, d.frameHeader.Width, d.frameHeader.Height)).(*image.YCbCr) + d.perMBFilterParams = make([]filterParam, d.mbw*d.mbh) + d.upMB = make([]mb, d.mbw) +} + +// parseSegmentHeader parses the segment header, as specified in section 9.3. +func (d *Decoder) parseSegmentHeader() { + d.segmentHeader.useSegment = d.fp.readBit(uniformProb) + if !d.segmentHeader.useSegment { + d.segmentHeader.updateMap = false + return + } + d.segmentHeader.updateMap = d.fp.readBit(uniformProb) + if d.fp.readBit(uniformProb) { + d.segmentHeader.relativeDelta = !d.fp.readBit(uniformProb) + for i := range d.segmentHeader.quantizer { + d.segmentHeader.quantizer[i] = int8(d.fp.readOptionalInt(uniformProb, 7)) + } + for i := range d.segmentHeader.filterStrength { + d.segmentHeader.filterStrength[i] = int8(d.fp.readOptionalInt(uniformProb, 6)) + } + } + if !d.segmentHeader.updateMap { + return + } + for i := range d.segmentHeader.prob { + if d.fp.readBit(uniformProb) { + d.segmentHeader.prob[i] = uint8(d.fp.readUint(uniformProb, 8)) + } else { + d.segmentHeader.prob[i] = 0xff + } + } +} + +// parseFilterHeader parses the filter header, as specified in section 9.4. +func (d *Decoder) parseFilterHeader() { + d.filterHeader.simple = d.fp.readBit(uniformProb) + d.filterHeader.level = int8(d.fp.readUint(uniformProb, 6)) + d.filterHeader.sharpness = uint8(d.fp.readUint(uniformProb, 3)) + d.filterHeader.useLFDelta = d.fp.readBit(uniformProb) + if d.filterHeader.useLFDelta && d.fp.readBit(uniformProb) { + for i := range d.filterHeader.refLFDelta { + d.filterHeader.refLFDelta[i] = int8(d.fp.readOptionalInt(uniformProb, 6)) + } + for i := range d.filterHeader.modeLFDelta { + d.filterHeader.modeLFDelta[i] = int8(d.fp.readOptionalInt(uniformProb, 6)) + } + } + if d.filterHeader.level == 0 { + return + } + if d.segmentHeader.useSegment { + for i := range d.filterHeader.perSegmentLevel { + strength := d.segmentHeader.filterStrength[i] + if d.segmentHeader.relativeDelta { + strength += d.filterHeader.level + } + d.filterHeader.perSegmentLevel[i] = strength + } + } else { + d.filterHeader.perSegmentLevel[0] = d.filterHeader.level + } + d.computeFilterParams() +} + +// parseOtherPartitions parses the other partitions, as specified in section 9.5. +func (d *Decoder) parseOtherPartitions() error { + const maxNOP = 1 << 3 + var partLens [maxNOP]int + d.nOP = 1 << d.fp.readUint(uniformProb, 2) + + // The final partition length is implied by the the remaining chunk data + // (d.r.n) and the other d.nOP-1 partition lengths. Those d.nOP-1 partition + // lengths are stored as 24-bit uints, i.e. up to 16 MiB per partition. + n := 3 * (d.nOP - 1) + partLens[d.nOP-1] = d.r.n - n + if partLens[d.nOP-1] < 0 { + return io.ErrUnexpectedEOF + } + if n > 0 { + buf := make([]byte, n) + if err := d.r.ReadFull(buf); err != nil { + return err + } + for i := 0; i < d.nOP-1; i++ { + pl := int(buf[3*i+0]) | int(buf[3*i+1])<<8 | int(buf[3*i+2])<<16 + if pl > partLens[d.nOP-1] { + return io.ErrUnexpectedEOF + } + partLens[i] = pl + partLens[d.nOP-1] -= pl + } + } + + // We check if the final partition length can also fit into a 24-bit uint. + // Strictly speaking, this isn't part of the spec, but it guards against a + // malicious WEBP image that is too large to ReadFull the encoded DCT + // coefficients into memory, whether that's because the actual WEBP file is + // too large, or whether its RIFF metadata lists too large a chunk. + if 1<<24 <= partLens[d.nOP-1] { + return errors.New("vp8: too much data to decode") + } + + buf := make([]byte, d.r.n) + if err := d.r.ReadFull(buf); err != nil { + return err + } + for i, pl := range partLens { + if i == d.nOP { + break + } + d.op[i].init(buf[:pl]) + buf = buf[pl:] + } + return nil +} + +// parseOtherHeaders parses header information other than the frame header. +func (d *Decoder) parseOtherHeaders() error { + // Initialize and parse the first partition. + firstPartition := make([]byte, d.frameHeader.FirstPartitionLen) + if err := d.r.ReadFull(firstPartition); err != nil { + return err + } + d.fp.init(firstPartition) + if d.frameHeader.KeyFrame { + // Read and ignore the color space and pixel clamp values. They are + // specified in section 9.2, but are unimplemented. + d.fp.readBit(uniformProb) + d.fp.readBit(uniformProb) + } + d.parseSegmentHeader() + d.parseFilterHeader() + if err := d.parseOtherPartitions(); err != nil { + return err + } + d.parseQuant() + if !d.frameHeader.KeyFrame { + // Golden and AltRef frames are specified in section 9.7. + // TODO(nigeltao): implement. Note that they are only used for video, not still images. + return errors.New("vp8: Golden / AltRef frames are not implemented") + } + // Read and ignore the refreshLastFrameBuffer bit, specified in section 9.8. + // It applies only to video, and not still images. + d.fp.readBit(uniformProb) + d.parseTokenProb() + d.useSkipProb = d.fp.readBit(uniformProb) + if d.useSkipProb { + d.skipProb = uint8(d.fp.readUint(uniformProb, 8)) + } + if d.fp.unexpectedEOF { + return io.ErrUnexpectedEOF + } + return nil +} + +// DecodeFrame decodes the frame and returns it as an YCbCr image. +// The image's contents are valid up until the next call to Decoder.Init. +func (d *Decoder) DecodeFrame() (*image.YCbCr, error) { + d.ensureImg() + if err := d.parseOtherHeaders(); err != nil { + return nil, err + } + // Reconstruct the rows. + for mbx := 0; mbx < d.mbw; mbx++ { + d.upMB[mbx] = mb{} + } + for mby := 0; mby < d.mbh; mby++ { + d.leftMB = mb{} + for mbx := 0; mbx < d.mbw; mbx++ { + skip := d.reconstruct(mbx, mby) + fs := d.filterParams[d.segment][btou(!d.usePredY16)] + fs.inner = fs.inner || !skip + d.perMBFilterParams[d.mbw*mby+mbx] = fs + } + } + if d.fp.unexpectedEOF { + return nil, io.ErrUnexpectedEOF + } + for i := 0; i < d.nOP; i++ { + if d.op[i].unexpectedEOF { + return nil, io.ErrUnexpectedEOF + } + } + // Apply the loop filter. + // + // Even if we are using per-segment levels, section 15 says that "loop + // filtering must be skipped entirely if loop_filter_level at either the + // frame header level or macroblock override level is 0". + if d.filterHeader.level != 0 { + if d.filterHeader.simple { + d.simpleFilter() + } else { + d.normalFilter() + } + } + return d.img, nil +} diff --git a/vendor/golang.org/x/image/vp8/filter.go b/vendor/golang.org/x/image/vp8/filter.go new file mode 100644 index 0000000..e34a811 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/filter.go @@ -0,0 +1,273 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// filter2 modifies a 2-pixel wide or 2-pixel high band along an edge. +func filter2(pix []byte, level, index, iStep, jStep int) { + for n := 16; n > 0; n, index = n-1, index+iStep { + p1 := int(pix[index-2*jStep]) + p0 := int(pix[index-1*jStep]) + q0 := int(pix[index+0*jStep]) + q1 := int(pix[index+1*jStep]) + if abs(p0-q0)<<1+abs(p1-q1)>>1 > level { + continue + } + a := 3*(q0-p0) + clamp127(p1-q1) + a1 := clamp15((a + 4) >> 3) + a2 := clamp15((a + 3) >> 3) + pix[index-1*jStep] = clamp255(p0 + a2) + pix[index+0*jStep] = clamp255(q0 - a1) + } +} + +// filter246 modifies a 2-, 4- or 6-pixel wide or high band along an edge. +func filter246(pix []byte, n, level, ilevel, hlevel, index, iStep, jStep int, fourNotSix bool) { + for ; n > 0; n, index = n-1, index+iStep { + p3 := int(pix[index-4*jStep]) + p2 := int(pix[index-3*jStep]) + p1 := int(pix[index-2*jStep]) + p0 := int(pix[index-1*jStep]) + q0 := int(pix[index+0*jStep]) + q1 := int(pix[index+1*jStep]) + q2 := int(pix[index+2*jStep]) + q3 := int(pix[index+3*jStep]) + if abs(p0-q0)<<1+abs(p1-q1)>>1 > level { + continue + } + if abs(p3-p2) > ilevel || + abs(p2-p1) > ilevel || + abs(p1-p0) > ilevel || + abs(q1-q0) > ilevel || + abs(q2-q1) > ilevel || + abs(q3-q2) > ilevel { + continue + } + if abs(p1-p0) > hlevel || abs(q1-q0) > hlevel { + // Filter 2 pixels. + a := 3*(q0-p0) + clamp127(p1-q1) + a1 := clamp15((a + 4) >> 3) + a2 := clamp15((a + 3) >> 3) + pix[index-1*jStep] = clamp255(p0 + a2) + pix[index+0*jStep] = clamp255(q0 - a1) + } else if fourNotSix { + // Filter 4 pixels. + a := 3 * (q0 - p0) + a1 := clamp15((a + 4) >> 3) + a2 := clamp15((a + 3) >> 3) + a3 := (a1 + 1) >> 1 + pix[index-2*jStep] = clamp255(p1 + a3) + pix[index-1*jStep] = clamp255(p0 + a2) + pix[index+0*jStep] = clamp255(q0 - a1) + pix[index+1*jStep] = clamp255(q1 - a3) + } else { + // Filter 6 pixels. + a := clamp127(3*(q0-p0) + clamp127(p1-q1)) + a1 := (27*a + 63) >> 7 + a2 := (18*a + 63) >> 7 + a3 := (9*a + 63) >> 7 + pix[index-3*jStep] = clamp255(p2 + a3) + pix[index-2*jStep] = clamp255(p1 + a2) + pix[index-1*jStep] = clamp255(p0 + a1) + pix[index+0*jStep] = clamp255(q0 - a1) + pix[index+1*jStep] = clamp255(q1 - a2) + pix[index+2*jStep] = clamp255(q2 - a3) + } + } +} + +// simpleFilter implements the simple filter, as specified in section 15.2. +func (d *Decoder) simpleFilter() { + for mby := 0; mby < d.mbh; mby++ { + for mbx := 0; mbx < d.mbw; mbx++ { + f := d.perMBFilterParams[d.mbw*mby+mbx] + if f.level == 0 { + continue + } + l := int(f.level) + yIndex := (mby*d.img.YStride + mbx) * 16 + if mbx > 0 { + filter2(d.img.Y, l+4, yIndex, d.img.YStride, 1) + } + if f.inner { + filter2(d.img.Y, l, yIndex+0x4, d.img.YStride, 1) + filter2(d.img.Y, l, yIndex+0x8, d.img.YStride, 1) + filter2(d.img.Y, l, yIndex+0xc, d.img.YStride, 1) + } + if mby > 0 { + filter2(d.img.Y, l+4, yIndex, 1, d.img.YStride) + } + if f.inner { + filter2(d.img.Y, l, yIndex+d.img.YStride*0x4, 1, d.img.YStride) + filter2(d.img.Y, l, yIndex+d.img.YStride*0x8, 1, d.img.YStride) + filter2(d.img.Y, l, yIndex+d.img.YStride*0xc, 1, d.img.YStride) + } + } + } +} + +// normalFilter implements the normal filter, as specified in section 15.3. +func (d *Decoder) normalFilter() { + for mby := 0; mby < d.mbh; mby++ { + for mbx := 0; mbx < d.mbw; mbx++ { + f := d.perMBFilterParams[d.mbw*mby+mbx] + if f.level == 0 { + continue + } + l, il, hl := int(f.level), int(f.ilevel), int(f.hlevel) + yIndex := (mby*d.img.YStride + mbx) * 16 + cIndex := (mby*d.img.CStride + mbx) * 8 + if mbx > 0 { + filter246(d.img.Y, 16, l+4, il, hl, yIndex, d.img.YStride, 1, false) + filter246(d.img.Cb, 8, l+4, il, hl, cIndex, d.img.CStride, 1, false) + filter246(d.img.Cr, 8, l+4, il, hl, cIndex, d.img.CStride, 1, false) + } + if f.inner { + filter246(d.img.Y, 16, l, il, hl, yIndex+0x4, d.img.YStride, 1, true) + filter246(d.img.Y, 16, l, il, hl, yIndex+0x8, d.img.YStride, 1, true) + filter246(d.img.Y, 16, l, il, hl, yIndex+0xc, d.img.YStride, 1, true) + filter246(d.img.Cb, 8, l, il, hl, cIndex+0x4, d.img.CStride, 1, true) + filter246(d.img.Cr, 8, l, il, hl, cIndex+0x4, d.img.CStride, 1, true) + } + if mby > 0 { + filter246(d.img.Y, 16, l+4, il, hl, yIndex, 1, d.img.YStride, false) + filter246(d.img.Cb, 8, l+4, il, hl, cIndex, 1, d.img.CStride, false) + filter246(d.img.Cr, 8, l+4, il, hl, cIndex, 1, d.img.CStride, false) + } + if f.inner { + filter246(d.img.Y, 16, l, il, hl, yIndex+d.img.YStride*0x4, 1, d.img.YStride, true) + filter246(d.img.Y, 16, l, il, hl, yIndex+d.img.YStride*0x8, 1, d.img.YStride, true) + filter246(d.img.Y, 16, l, il, hl, yIndex+d.img.YStride*0xc, 1, d.img.YStride, true) + filter246(d.img.Cb, 8, l, il, hl, cIndex+d.img.CStride*0x4, 1, d.img.CStride, true) + filter246(d.img.Cr, 8, l, il, hl, cIndex+d.img.CStride*0x4, 1, d.img.CStride, true) + } + } + } +} + +// filterParam holds the loop filter parameters for a macroblock. +type filterParam struct { + // The first three fields are thresholds used by the loop filter to smooth + // over the edges and interior of a macroblock. level is used by both the + // simple and normal filters. The inner level and high edge variance level + // are only used by the normal filter. + level, ilevel, hlevel uint8 + // inner is whether the inner loop filter cannot be optimized out as a + // no-op for this particular macroblock. + inner bool +} + +// computeFilterParams computes the loop filter parameters, as specified in +// section 15.4. +func (d *Decoder) computeFilterParams() { + for i := range d.filterParams { + baseLevel := d.filterHeader.level + if d.segmentHeader.useSegment { + baseLevel = d.segmentHeader.filterStrength[i] + if d.segmentHeader.relativeDelta { + baseLevel += d.filterHeader.level + } + } + + for j := range d.filterParams[i] { + p := &d.filterParams[i][j] + p.inner = j != 0 + level := baseLevel + if d.filterHeader.useLFDelta { + // The libwebp C code has a "TODO: only CURRENT is handled for now." + level += d.filterHeader.refLFDelta[0] + if j != 0 { + level += d.filterHeader.modeLFDelta[0] + } + } + if level <= 0 { + p.level = 0 + continue + } + if level > 63 { + level = 63 + } + ilevel := level + if d.filterHeader.sharpness > 0 { + if d.filterHeader.sharpness > 4 { + ilevel >>= 2 + } else { + ilevel >>= 1 + } + if x := int8(9 - d.filterHeader.sharpness); ilevel > x { + ilevel = x + } + } + if ilevel < 1 { + ilevel = 1 + } + p.ilevel = uint8(ilevel) + p.level = uint8(2*level + ilevel) + if d.frameHeader.KeyFrame { + if level < 15 { + p.hlevel = 0 + } else if level < 40 { + p.hlevel = 1 + } else { + p.hlevel = 2 + } + } else { + if level < 15 { + p.hlevel = 0 + } else if level < 20 { + p.hlevel = 1 + } else if level < 40 { + p.hlevel = 2 + } else { + p.hlevel = 3 + } + } + } + } +} + +// intSize is either 32 or 64. +const intSize = 32 << (^uint(0) >> 63) + +func abs(x int) int { + // m := -1 if x < 0. m := 0 otherwise. + m := x >> (intSize - 1) + + // In two's complement representation, the negative number + // of any number (except the smallest one) can be computed + // by flipping all the bits and add 1. This is faster than + // code with a branch. + // See Hacker's Delight, section 2-4. + return (x ^ m) - m +} + +func clamp15(x int) int { + if x < -16 { + return -16 + } + if x > 15 { + return 15 + } + return x +} + +func clamp127(x int) int { + if x < -128 { + return -128 + } + if x > 127 { + return 127 + } + return x +} + +func clamp255(x int) uint8 { + if x < 0 { + return 0 + } + if x > 255 { + return 255 + } + return uint8(x) +} diff --git a/vendor/golang.org/x/image/vp8/idct.go b/vendor/golang.org/x/image/vp8/idct.go new file mode 100644 index 0000000..929af2c --- /dev/null +++ b/vendor/golang.org/x/image/vp8/idct.go @@ -0,0 +1,98 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file implements the inverse Discrete Cosine Transform and the inverse +// Walsh Hadamard Transform (WHT), as specified in sections 14.3 and 14.4. + +func clip8(i int32) uint8 { + if i < 0 { + return 0 + } + if i > 255 { + return 255 + } + return uint8(i) +} + +func (z *Decoder) inverseDCT4(y, x, coeffBase int) { + const ( + c1 = 85627 // 65536 * cos(pi/8) * sqrt(2). + c2 = 35468 // 65536 * sin(pi/8) * sqrt(2). + ) + var m [4][4]int32 + for i := 0; i < 4; i++ { + a := int32(z.coeff[coeffBase+0]) + int32(z.coeff[coeffBase+8]) + b := int32(z.coeff[coeffBase+0]) - int32(z.coeff[coeffBase+8]) + c := (int32(z.coeff[coeffBase+4])*c2)>>16 - (int32(z.coeff[coeffBase+12])*c1)>>16 + d := (int32(z.coeff[coeffBase+4])*c1)>>16 + (int32(z.coeff[coeffBase+12])*c2)>>16 + m[i][0] = a + d + m[i][1] = b + c + m[i][2] = b - c + m[i][3] = a - d + coeffBase++ + } + for j := 0; j < 4; j++ { + dc := m[0][j] + 4 + a := dc + m[2][j] + b := dc - m[2][j] + c := (m[1][j]*c2)>>16 - (m[3][j]*c1)>>16 + d := (m[1][j]*c1)>>16 + (m[3][j]*c2)>>16 + z.ybr[y+j][x+0] = clip8(int32(z.ybr[y+j][x+0]) + (a+d)>>3) + z.ybr[y+j][x+1] = clip8(int32(z.ybr[y+j][x+1]) + (b+c)>>3) + z.ybr[y+j][x+2] = clip8(int32(z.ybr[y+j][x+2]) + (b-c)>>3) + z.ybr[y+j][x+3] = clip8(int32(z.ybr[y+j][x+3]) + (a-d)>>3) + } +} + +func (z *Decoder) inverseDCT4DCOnly(y, x, coeffBase int) { + dc := (int32(z.coeff[coeffBase+0]) + 4) >> 3 + for j := 0; j < 4; j++ { + for i := 0; i < 4; i++ { + z.ybr[y+j][x+i] = clip8(int32(z.ybr[y+j][x+i]) + dc) + } + } +} + +func (z *Decoder) inverseDCT8(y, x, coeffBase int) { + z.inverseDCT4(y+0, x+0, coeffBase+0*16) + z.inverseDCT4(y+0, x+4, coeffBase+1*16) + z.inverseDCT4(y+4, x+0, coeffBase+2*16) + z.inverseDCT4(y+4, x+4, coeffBase+3*16) +} + +func (z *Decoder) inverseDCT8DCOnly(y, x, coeffBase int) { + z.inverseDCT4DCOnly(y+0, x+0, coeffBase+0*16) + z.inverseDCT4DCOnly(y+0, x+4, coeffBase+1*16) + z.inverseDCT4DCOnly(y+4, x+0, coeffBase+2*16) + z.inverseDCT4DCOnly(y+4, x+4, coeffBase+3*16) +} + +func (d *Decoder) inverseWHT16() { + var m [16]int32 + for i := 0; i < 4; i++ { + a0 := int32(d.coeff[384+0+i]) + int32(d.coeff[384+12+i]) + a1 := int32(d.coeff[384+4+i]) + int32(d.coeff[384+8+i]) + a2 := int32(d.coeff[384+4+i]) - int32(d.coeff[384+8+i]) + a3 := int32(d.coeff[384+0+i]) - int32(d.coeff[384+12+i]) + m[0+i] = a0 + a1 + m[8+i] = a0 - a1 + m[4+i] = a3 + a2 + m[12+i] = a3 - a2 + } + out := 0 + for i := 0; i < 4; i++ { + dc := m[0+i*4] + 3 + a0 := dc + m[3+i*4] + a1 := m[1+i*4] + m[2+i*4] + a2 := m[1+i*4] - m[2+i*4] + a3 := dc - m[3+i*4] + d.coeff[out+0] = int16((a0 + a1) >> 3) + d.coeff[out+16] = int16((a3 + a2) >> 3) + d.coeff[out+32] = int16((a0 - a1) >> 3) + d.coeff[out+48] = int16((a3 - a2) >> 3) + out += 64 + } +} diff --git a/vendor/golang.org/x/image/vp8/partition.go b/vendor/golang.org/x/image/vp8/partition.go new file mode 100644 index 0000000..72288bd --- /dev/null +++ b/vendor/golang.org/x/image/vp8/partition.go @@ -0,0 +1,129 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// Each VP8 frame consists of between 2 and 9 bitstream partitions. +// Each partition is byte-aligned and is independently arithmetic-encoded. +// +// This file implements decoding a partition's bitstream, as specified in +// chapter 7. The implementation follows libwebp's approach instead of the +// specification's reference C implementation. For example, we use a look-up +// table instead of a for loop to recalibrate the encoded range. + +var ( + lutShift = [127]uint8{ + 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, + 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + } + lutRangeM1 = [127]uint8{ + 127, + 127, 191, + 127, 159, 191, 223, + 127, 143, 159, 175, 191, 207, 223, 239, + 127, 135, 143, 151, 159, 167, 175, 183, 191, 199, 207, 215, 223, 231, 239, 247, + 127, 131, 135, 139, 143, 147, 151, 155, 159, 163, 167, 171, 175, 179, 183, 187, + 191, 195, 199, 203, 207, 211, 215, 219, 223, 227, 231, 235, 239, 243, 247, 251, + 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, + 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 181, 183, 185, 187, 189, + 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, + 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, + } +) + +// uniformProb represents a 50% probability that the next bit is 0. +const uniformProb = 128 + +// partition holds arithmetic-coded bits. +type partition struct { + // buf is the input bytes. + buf []byte + // r is how many of buf's bytes have been consumed. + r int + // rangeM1 is range minus 1, where range is in the arithmetic coding sense, + // not the Go language sense. + rangeM1 uint32 + // bits and nBits hold those bits shifted out of buf but not yet consumed. + bits uint32 + nBits uint8 + // unexpectedEOF tells whether we tried to read past buf. + unexpectedEOF bool +} + +// init initializes the partition. +func (p *partition) init(buf []byte) { + p.buf = buf + p.r = 0 + p.rangeM1 = 254 + p.bits = 0 + p.nBits = 0 + p.unexpectedEOF = false +} + +// readBit returns the next bit. +func (p *partition) readBit(prob uint8) bool { + if p.nBits < 8 { + if p.r >= len(p.buf) { + p.unexpectedEOF = true + return false + } + // Expression split for 386 compiler. + x := uint32(p.buf[p.r]) + p.bits |= x << (8 - p.nBits) + p.r++ + p.nBits += 8 + } + split := (p.rangeM1*uint32(prob))>>8 + 1 + bit := p.bits >= split<<8 + if bit { + p.rangeM1 -= split + p.bits -= split << 8 + } else { + p.rangeM1 = split - 1 + } + if p.rangeM1 < 127 { + shift := lutShift[p.rangeM1] + p.rangeM1 = uint32(lutRangeM1[p.rangeM1]) + p.bits <<= shift + p.nBits -= shift + } + return bit +} + +// readUint returns the next n-bit unsigned integer. +func (p *partition) readUint(prob, n uint8) uint32 { + var u uint32 + for n > 0 { + n-- + if p.readBit(prob) { + u |= 1 << n + } + } + return u +} + +// readInt returns the next n-bit signed integer. +func (p *partition) readInt(prob, n uint8) int32 { + u := p.readUint(prob, n) + b := p.readBit(prob) + if b { + return -int32(u) + } + return int32(u) +} + +// readOptionalInt returns the next n-bit signed integer in an encoding +// where the likely result is zero. +func (p *partition) readOptionalInt(prob, n uint8) int32 { + if !p.readBit(prob) { + return 0 + } + return p.readInt(prob, n) +} diff --git a/vendor/golang.org/x/image/vp8/pred.go b/vendor/golang.org/x/image/vp8/pred.go new file mode 100644 index 0000000..58c2689 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/pred.go @@ -0,0 +1,201 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file implements parsing the predictor modes, as specified in chapter +// 11. + +func (d *Decoder) parsePredModeY16(mbx int) { + var p uint8 + if !d.fp.readBit(156) { + if !d.fp.readBit(163) { + p = predDC + } else { + p = predVE + } + } else if !d.fp.readBit(128) { + p = predHE + } else { + p = predTM + } + for i := 0; i < 4; i++ { + d.upMB[mbx].pred[i] = p + d.leftMB.pred[i] = p + } + d.predY16 = p +} + +func (d *Decoder) parsePredModeC8() { + if !d.fp.readBit(142) { + d.predC8 = predDC + } else if !d.fp.readBit(114) { + d.predC8 = predVE + } else if !d.fp.readBit(183) { + d.predC8 = predHE + } else { + d.predC8 = predTM + } +} + +func (d *Decoder) parsePredModeY4(mbx int) { + for j := 0; j < 4; j++ { + p := d.leftMB.pred[j] + for i := 0; i < 4; i++ { + prob := &predProb[d.upMB[mbx].pred[i]][p] + if !d.fp.readBit(prob[0]) { + p = predDC + } else if !d.fp.readBit(prob[1]) { + p = predTM + } else if !d.fp.readBit(prob[2]) { + p = predVE + } else if !d.fp.readBit(prob[3]) { + if !d.fp.readBit(prob[4]) { + p = predHE + } else if !d.fp.readBit(prob[5]) { + p = predRD + } else { + p = predVR + } + } else if !d.fp.readBit(prob[6]) { + p = predLD + } else if !d.fp.readBit(prob[7]) { + p = predVL + } else if !d.fp.readBit(prob[8]) { + p = predHD + } else { + p = predHU + } + d.predY4[j][i] = p + d.upMB[mbx].pred[i] = p + } + d.leftMB.pred[j] = p + } +} + +// predProb are the probabilities to decode a 4x4 region's predictor mode given +// the predictor modes of the regions above and left of it. +// These values are specified in section 11.5. +var predProb = [nPred][nPred][9]uint8{ + { + {231, 120, 48, 89, 115, 113, 120, 152, 112}, + {152, 179, 64, 126, 170, 118, 46, 70, 95}, + {175, 69, 143, 80, 85, 82, 72, 155, 103}, + {56, 58, 10, 171, 218, 189, 17, 13, 152}, + {114, 26, 17, 163, 44, 195, 21, 10, 173}, + {121, 24, 80, 195, 26, 62, 44, 64, 85}, + {144, 71, 10, 38, 171, 213, 144, 34, 26}, + {170, 46, 55, 19, 136, 160, 33, 206, 71}, + {63, 20, 8, 114, 114, 208, 12, 9, 226}, + {81, 40, 11, 96, 182, 84, 29, 16, 36}, + }, + { + {134, 183, 89, 137, 98, 101, 106, 165, 148}, + {72, 187, 100, 130, 157, 111, 32, 75, 80}, + {66, 102, 167, 99, 74, 62, 40, 234, 128}, + {41, 53, 9, 178, 241, 141, 26, 8, 107}, + {74, 43, 26, 146, 73, 166, 49, 23, 157}, + {65, 38, 105, 160, 51, 52, 31, 115, 128}, + {104, 79, 12, 27, 217, 255, 87, 17, 7}, + {87, 68, 71, 44, 114, 51, 15, 186, 23}, + {47, 41, 14, 110, 182, 183, 21, 17, 194}, + {66, 45, 25, 102, 197, 189, 23, 18, 22}, + }, + { + {88, 88, 147, 150, 42, 46, 45, 196, 205}, + {43, 97, 183, 117, 85, 38, 35, 179, 61}, + {39, 53, 200, 87, 26, 21, 43, 232, 171}, + {56, 34, 51, 104, 114, 102, 29, 93, 77}, + {39, 28, 85, 171, 58, 165, 90, 98, 64}, + {34, 22, 116, 206, 23, 34, 43, 166, 73}, + {107, 54, 32, 26, 51, 1, 81, 43, 31}, + {68, 25, 106, 22, 64, 171, 36, 225, 114}, + {34, 19, 21, 102, 132, 188, 16, 76, 124}, + {62, 18, 78, 95, 85, 57, 50, 48, 51}, + }, + { + {193, 101, 35, 159, 215, 111, 89, 46, 111}, + {60, 148, 31, 172, 219, 228, 21, 18, 111}, + {112, 113, 77, 85, 179, 255, 38, 120, 114}, + {40, 42, 1, 196, 245, 209, 10, 25, 109}, + {88, 43, 29, 140, 166, 213, 37, 43, 154}, + {61, 63, 30, 155, 67, 45, 68, 1, 209}, + {100, 80, 8, 43, 154, 1, 51, 26, 71}, + {142, 78, 78, 16, 255, 128, 34, 197, 171}, + {41, 40, 5, 102, 211, 183, 4, 1, 221}, + {51, 50, 17, 168, 209, 192, 23, 25, 82}, + }, + { + {138, 31, 36, 171, 27, 166, 38, 44, 229}, + {67, 87, 58, 169, 82, 115, 26, 59, 179}, + {63, 59, 90, 180, 59, 166, 93, 73, 154}, + {40, 40, 21, 116, 143, 209, 34, 39, 175}, + {47, 15, 16, 183, 34, 223, 49, 45, 183}, + {46, 17, 33, 183, 6, 98, 15, 32, 183}, + {57, 46, 22, 24, 128, 1, 54, 17, 37}, + {65, 32, 73, 115, 28, 128, 23, 128, 205}, + {40, 3, 9, 115, 51, 192, 18, 6, 223}, + {87, 37, 9, 115, 59, 77, 64, 21, 47}, + }, + { + {104, 55, 44, 218, 9, 54, 53, 130, 226}, + {64, 90, 70, 205, 40, 41, 23, 26, 57}, + {54, 57, 112, 184, 5, 41, 38, 166, 213}, + {30, 34, 26, 133, 152, 116, 10, 32, 134}, + {39, 19, 53, 221, 26, 114, 32, 73, 255}, + {31, 9, 65, 234, 2, 15, 1, 118, 73}, + {75, 32, 12, 51, 192, 255, 160, 43, 51}, + {88, 31, 35, 67, 102, 85, 55, 186, 85}, + {56, 21, 23, 111, 59, 205, 45, 37, 192}, + {55, 38, 70, 124, 73, 102, 1, 34, 98}, + }, + { + {125, 98, 42, 88, 104, 85, 117, 175, 82}, + {95, 84, 53, 89, 128, 100, 113, 101, 45}, + {75, 79, 123, 47, 51, 128, 81, 171, 1}, + {57, 17, 5, 71, 102, 57, 53, 41, 49}, + {38, 33, 13, 121, 57, 73, 26, 1, 85}, + {41, 10, 67, 138, 77, 110, 90, 47, 114}, + {115, 21, 2, 10, 102, 255, 166, 23, 6}, + {101, 29, 16, 10, 85, 128, 101, 196, 26}, + {57, 18, 10, 102, 102, 213, 34, 20, 43}, + {117, 20, 15, 36, 163, 128, 68, 1, 26}, + }, + { + {102, 61, 71, 37, 34, 53, 31, 243, 192}, + {69, 60, 71, 38, 73, 119, 28, 222, 37}, + {68, 45, 128, 34, 1, 47, 11, 245, 171}, + {62, 17, 19, 70, 146, 85, 55, 62, 70}, + {37, 43, 37, 154, 100, 163, 85, 160, 1}, + {63, 9, 92, 136, 28, 64, 32, 201, 85}, + {75, 15, 9, 9, 64, 255, 184, 119, 16}, + {86, 6, 28, 5, 64, 255, 25, 248, 1}, + {56, 8, 17, 132, 137, 255, 55, 116, 128}, + {58, 15, 20, 82, 135, 57, 26, 121, 40}, + }, + { + {164, 50, 31, 137, 154, 133, 25, 35, 218}, + {51, 103, 44, 131, 131, 123, 31, 6, 158}, + {86, 40, 64, 135, 148, 224, 45, 183, 128}, + {22, 26, 17, 131, 240, 154, 14, 1, 209}, + {45, 16, 21, 91, 64, 222, 7, 1, 197}, + {56, 21, 39, 155, 60, 138, 23, 102, 213}, + {83, 12, 13, 54, 192, 255, 68, 47, 28}, + {85, 26, 85, 85, 128, 128, 32, 146, 171}, + {18, 11, 7, 63, 144, 171, 4, 4, 246}, + {35, 27, 10, 146, 174, 171, 12, 26, 128}, + }, + { + {190, 80, 35, 99, 180, 80, 126, 54, 45}, + {85, 126, 47, 87, 176, 51, 41, 20, 32}, + {101, 75, 128, 139, 118, 146, 116, 128, 85}, + {56, 41, 15, 176, 236, 85, 37, 9, 62}, + {71, 30, 17, 119, 118, 255, 17, 18, 138}, + {101, 38, 60, 138, 55, 70, 43, 26, 142}, + {146, 36, 19, 30, 171, 255, 97, 27, 20}, + {138, 45, 61, 62, 219, 1, 81, 188, 64}, + {32, 41, 20, 117, 151, 142, 20, 21, 163}, + {112, 19, 12, 61, 195, 128, 48, 4, 24}, + }, +} diff --git a/vendor/golang.org/x/image/vp8/predfunc.go b/vendor/golang.org/x/image/vp8/predfunc.go new file mode 100644 index 0000000..f899958 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/predfunc.go @@ -0,0 +1,553 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file implements the predicition functions, as specified in chapter 12. +// +// For each macroblock (of 1x16x16 luma and 2x8x8 chroma coefficients), the +// luma values are either predicted as one large 16x16 region or 16 separate +// 4x4 regions. The chroma values are always predicted as one 8x8 region. +// +// For 4x4 regions, the target block's predicted values (Xs) are a function of +// its previously-decoded top and left border values, as well as a number of +// pixels from the top-right: +// +// a b c d e f g h +// p X X X X +// q X X X X +// r X X X X +// s X X X X +// +// The predictor modes are: +// - DC: all Xs = (b + c + d + e + p + q + r + s + 4) / 8. +// - TM: the first X = (b + p - a), the second X = (c + p - a), and so on. +// - VE: each X = the weighted average of its column's top value and that +// value's neighbors, i.e. averages of abc, bcd, cde or def. +// - HE: similar to VE except rows instead of columns, and the final row is +// an average of r, s and s. +// - RD, VR, LD, VL, HD, HU: these diagonal modes ("Right Down", "Vertical +// Right", etc) are more complicated and are described in section 12.3. +// All Xs are clipped to the range [0, 255]. +// +// For 8x8 and 16x16 regions, the target block's predicted values are a +// function of the top and left border values without the top-right overhang, +// i.e. without the 8x8 or 16x16 equivalent of f, g and h. Furthermore: +// - There are no diagonal predictor modes, only DC, TM, VE and HE. +// - The DC mode has variants for macroblocks in the top row and/or left +// column, i.e. for macroblocks with mby == 0 || mbx == 0. +// - The VE and HE modes take only the column top or row left values; they do +// not smooth that top/left value with its neighbors. + +// nPred is the number of predictor modes, not including the Top/Left versions +// of the DC predictor mode. +const nPred = 10 + +const ( + predDC = iota + predTM + predVE + predHE + predRD + predVR + predLD + predVL + predHD + predHU + predDCTop + predDCLeft + predDCTopLeft +) + +func checkTopLeftPred(mbx, mby int, p uint8) uint8 { + if p != predDC { + return p + } + if mbx == 0 { + if mby == 0 { + return predDCTopLeft + } + return predDCLeft + } + if mby == 0 { + return predDCTop + } + return predDC +} + +var predFunc4 = [...]func(*Decoder, int, int){ + predFunc4DC, + predFunc4TM, + predFunc4VE, + predFunc4HE, + predFunc4RD, + predFunc4VR, + predFunc4LD, + predFunc4VL, + predFunc4HD, + predFunc4HU, + nil, + nil, + nil, +} + +var predFunc8 = [...]func(*Decoder, int, int){ + predFunc8DC, + predFunc8TM, + predFunc8VE, + predFunc8HE, + nil, + nil, + nil, + nil, + nil, + nil, + predFunc8DCTop, + predFunc8DCLeft, + predFunc8DCTopLeft, +} + +var predFunc16 = [...]func(*Decoder, int, int){ + predFunc16DC, + predFunc16TM, + predFunc16VE, + predFunc16HE, + nil, + nil, + nil, + nil, + nil, + nil, + predFunc16DCTop, + predFunc16DCLeft, + predFunc16DCTopLeft, +} + +func predFunc4DC(z *Decoder, y, x int) { + sum := uint32(4) + for i := 0; i < 4; i++ { + sum += uint32(z.ybr[y-1][x+i]) + } + for j := 0; j < 4; j++ { + sum += uint32(z.ybr[y+j][x-1]) + } + avg := uint8(sum / 8) + for j := 0; j < 4; j++ { + for i := 0; i < 4; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc4TM(z *Decoder, y, x int) { + delta0 := -int32(z.ybr[y-1][x-1]) + for j := 0; j < 4; j++ { + delta1 := delta0 + int32(z.ybr[y+j][x-1]) + for i := 0; i < 4; i++ { + delta2 := delta1 + int32(z.ybr[y-1][x+i]) + z.ybr[y+j][x+i] = uint8(clip(delta2, 0, 255)) + } + } +} + +func predFunc4VE(z *Decoder, y, x int) { + a := int32(z.ybr[y-1][x-1]) + b := int32(z.ybr[y-1][x+0]) + c := int32(z.ybr[y-1][x+1]) + d := int32(z.ybr[y-1][x+2]) + e := int32(z.ybr[y-1][x+3]) + f := int32(z.ybr[y-1][x+4]) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + cde := uint8((c + 2*d + e + 2) / 4) + def := uint8((d + 2*e + f + 2) / 4) + for j := 0; j < 4; j++ { + z.ybr[y+j][x+0] = abc + z.ybr[y+j][x+1] = bcd + z.ybr[y+j][x+2] = cde + z.ybr[y+j][x+3] = def + } +} + +func predFunc4HE(z *Decoder, y, x int) { + s := int32(z.ybr[y+3][x-1]) + r := int32(z.ybr[y+2][x-1]) + q := int32(z.ybr[y+1][x-1]) + p := int32(z.ybr[y+0][x-1]) + a := int32(z.ybr[y-1][x-1]) + ssr := uint8((s + 2*s + r + 2) / 4) + srq := uint8((s + 2*r + q + 2) / 4) + rqp := uint8((r + 2*q + p + 2) / 4) + apq := uint8((a + 2*p + q + 2) / 4) + for i := 0; i < 4; i++ { + z.ybr[y+0][x+i] = apq + z.ybr[y+1][x+i] = rqp + z.ybr[y+2][x+i] = srq + z.ybr[y+3][x+i] = ssr + } +} + +func predFunc4RD(z *Decoder, y, x int) { + s := int32(z.ybr[y+3][x-1]) + r := int32(z.ybr[y+2][x-1]) + q := int32(z.ybr[y+1][x-1]) + p := int32(z.ybr[y+0][x-1]) + a := int32(z.ybr[y-1][x-1]) + b := int32(z.ybr[y-1][x+0]) + c := int32(z.ybr[y-1][x+1]) + d := int32(z.ybr[y-1][x+2]) + e := int32(z.ybr[y-1][x+3]) + srq := uint8((s + 2*r + q + 2) / 4) + rqp := uint8((r + 2*q + p + 2) / 4) + qpa := uint8((q + 2*p + a + 2) / 4) + pab := uint8((p + 2*a + b + 2) / 4) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + cde := uint8((c + 2*d + e + 2) / 4) + z.ybr[y+0][x+0] = pab + z.ybr[y+0][x+1] = abc + z.ybr[y+0][x+2] = bcd + z.ybr[y+0][x+3] = cde + z.ybr[y+1][x+0] = qpa + z.ybr[y+1][x+1] = pab + z.ybr[y+1][x+2] = abc + z.ybr[y+1][x+3] = bcd + z.ybr[y+2][x+0] = rqp + z.ybr[y+2][x+1] = qpa + z.ybr[y+2][x+2] = pab + z.ybr[y+2][x+3] = abc + z.ybr[y+3][x+0] = srq + z.ybr[y+3][x+1] = rqp + z.ybr[y+3][x+2] = qpa + z.ybr[y+3][x+3] = pab +} + +func predFunc4VR(z *Decoder, y, x int) { + r := int32(z.ybr[y+2][x-1]) + q := int32(z.ybr[y+1][x-1]) + p := int32(z.ybr[y+0][x-1]) + a := int32(z.ybr[y-1][x-1]) + b := int32(z.ybr[y-1][x+0]) + c := int32(z.ybr[y-1][x+1]) + d := int32(z.ybr[y-1][x+2]) + e := int32(z.ybr[y-1][x+3]) + ab := uint8((a + b + 1) / 2) + bc := uint8((b + c + 1) / 2) + cd := uint8((c + d + 1) / 2) + de := uint8((d + e + 1) / 2) + rqp := uint8((r + 2*q + p + 2) / 4) + qpa := uint8((q + 2*p + a + 2) / 4) + pab := uint8((p + 2*a + b + 2) / 4) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + cde := uint8((c + 2*d + e + 2) / 4) + z.ybr[y+0][x+0] = ab + z.ybr[y+0][x+1] = bc + z.ybr[y+0][x+2] = cd + z.ybr[y+0][x+3] = de + z.ybr[y+1][x+0] = pab + z.ybr[y+1][x+1] = abc + z.ybr[y+1][x+2] = bcd + z.ybr[y+1][x+3] = cde + z.ybr[y+2][x+0] = qpa + z.ybr[y+2][x+1] = ab + z.ybr[y+2][x+2] = bc + z.ybr[y+2][x+3] = cd + z.ybr[y+3][x+0] = rqp + z.ybr[y+3][x+1] = pab + z.ybr[y+3][x+2] = abc + z.ybr[y+3][x+3] = bcd +} + +func predFunc4LD(z *Decoder, y, x int) { + a := int32(z.ybr[y-1][x+0]) + b := int32(z.ybr[y-1][x+1]) + c := int32(z.ybr[y-1][x+2]) + d := int32(z.ybr[y-1][x+3]) + e := int32(z.ybr[y-1][x+4]) + f := int32(z.ybr[y-1][x+5]) + g := int32(z.ybr[y-1][x+6]) + h := int32(z.ybr[y-1][x+7]) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + cde := uint8((c + 2*d + e + 2) / 4) + def := uint8((d + 2*e + f + 2) / 4) + efg := uint8((e + 2*f + g + 2) / 4) + fgh := uint8((f + 2*g + h + 2) / 4) + ghh := uint8((g + 2*h + h + 2) / 4) + z.ybr[y+0][x+0] = abc + z.ybr[y+0][x+1] = bcd + z.ybr[y+0][x+2] = cde + z.ybr[y+0][x+3] = def + z.ybr[y+1][x+0] = bcd + z.ybr[y+1][x+1] = cde + z.ybr[y+1][x+2] = def + z.ybr[y+1][x+3] = efg + z.ybr[y+2][x+0] = cde + z.ybr[y+2][x+1] = def + z.ybr[y+2][x+2] = efg + z.ybr[y+2][x+3] = fgh + z.ybr[y+3][x+0] = def + z.ybr[y+3][x+1] = efg + z.ybr[y+3][x+2] = fgh + z.ybr[y+3][x+3] = ghh +} + +func predFunc4VL(z *Decoder, y, x int) { + a := int32(z.ybr[y-1][x+0]) + b := int32(z.ybr[y-1][x+1]) + c := int32(z.ybr[y-1][x+2]) + d := int32(z.ybr[y-1][x+3]) + e := int32(z.ybr[y-1][x+4]) + f := int32(z.ybr[y-1][x+5]) + g := int32(z.ybr[y-1][x+6]) + h := int32(z.ybr[y-1][x+7]) + ab := uint8((a + b + 1) / 2) + bc := uint8((b + c + 1) / 2) + cd := uint8((c + d + 1) / 2) + de := uint8((d + e + 1) / 2) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + cde := uint8((c + 2*d + e + 2) / 4) + def := uint8((d + 2*e + f + 2) / 4) + efg := uint8((e + 2*f + g + 2) / 4) + fgh := uint8((f + 2*g + h + 2) / 4) + z.ybr[y+0][x+0] = ab + z.ybr[y+0][x+1] = bc + z.ybr[y+0][x+2] = cd + z.ybr[y+0][x+3] = de + z.ybr[y+1][x+0] = abc + z.ybr[y+1][x+1] = bcd + z.ybr[y+1][x+2] = cde + z.ybr[y+1][x+3] = def + z.ybr[y+2][x+0] = bc + z.ybr[y+2][x+1] = cd + z.ybr[y+2][x+2] = de + z.ybr[y+2][x+3] = efg + z.ybr[y+3][x+0] = bcd + z.ybr[y+3][x+1] = cde + z.ybr[y+3][x+2] = def + z.ybr[y+3][x+3] = fgh +} + +func predFunc4HD(z *Decoder, y, x int) { + s := int32(z.ybr[y+3][x-1]) + r := int32(z.ybr[y+2][x-1]) + q := int32(z.ybr[y+1][x-1]) + p := int32(z.ybr[y+0][x-1]) + a := int32(z.ybr[y-1][x-1]) + b := int32(z.ybr[y-1][x+0]) + c := int32(z.ybr[y-1][x+1]) + d := int32(z.ybr[y-1][x+2]) + sr := uint8((s + r + 1) / 2) + rq := uint8((r + q + 1) / 2) + qp := uint8((q + p + 1) / 2) + pa := uint8((p + a + 1) / 2) + srq := uint8((s + 2*r + q + 2) / 4) + rqp := uint8((r + 2*q + p + 2) / 4) + qpa := uint8((q + 2*p + a + 2) / 4) + pab := uint8((p + 2*a + b + 2) / 4) + abc := uint8((a + 2*b + c + 2) / 4) + bcd := uint8((b + 2*c + d + 2) / 4) + z.ybr[y+0][x+0] = pa + z.ybr[y+0][x+1] = pab + z.ybr[y+0][x+2] = abc + z.ybr[y+0][x+3] = bcd + z.ybr[y+1][x+0] = qp + z.ybr[y+1][x+1] = qpa + z.ybr[y+1][x+2] = pa + z.ybr[y+1][x+3] = pab + z.ybr[y+2][x+0] = rq + z.ybr[y+2][x+1] = rqp + z.ybr[y+2][x+2] = qp + z.ybr[y+2][x+3] = qpa + z.ybr[y+3][x+0] = sr + z.ybr[y+3][x+1] = srq + z.ybr[y+3][x+2] = rq + z.ybr[y+3][x+3] = rqp +} + +func predFunc4HU(z *Decoder, y, x int) { + s := int32(z.ybr[y+3][x-1]) + r := int32(z.ybr[y+2][x-1]) + q := int32(z.ybr[y+1][x-1]) + p := int32(z.ybr[y+0][x-1]) + pq := uint8((p + q + 1) / 2) + qr := uint8((q + r + 1) / 2) + rs := uint8((r + s + 1) / 2) + pqr := uint8((p + 2*q + r + 2) / 4) + qrs := uint8((q + 2*r + s + 2) / 4) + rss := uint8((r + 2*s + s + 2) / 4) + sss := uint8(s) + z.ybr[y+0][x+0] = pq + z.ybr[y+0][x+1] = pqr + z.ybr[y+0][x+2] = qr + z.ybr[y+0][x+3] = qrs + z.ybr[y+1][x+0] = qr + z.ybr[y+1][x+1] = qrs + z.ybr[y+1][x+2] = rs + z.ybr[y+1][x+3] = rss + z.ybr[y+2][x+0] = rs + z.ybr[y+2][x+1] = rss + z.ybr[y+2][x+2] = sss + z.ybr[y+2][x+3] = sss + z.ybr[y+3][x+0] = sss + z.ybr[y+3][x+1] = sss + z.ybr[y+3][x+2] = sss + z.ybr[y+3][x+3] = sss +} + +func predFunc8DC(z *Decoder, y, x int) { + sum := uint32(8) + for i := 0; i < 8; i++ { + sum += uint32(z.ybr[y-1][x+i]) + } + for j := 0; j < 8; j++ { + sum += uint32(z.ybr[y+j][x-1]) + } + avg := uint8(sum / 16) + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc8TM(z *Decoder, y, x int) { + delta0 := -int32(z.ybr[y-1][x-1]) + for j := 0; j < 8; j++ { + delta1 := delta0 + int32(z.ybr[y+j][x-1]) + for i := 0; i < 8; i++ { + delta2 := delta1 + int32(z.ybr[y-1][x+i]) + z.ybr[y+j][x+i] = uint8(clip(delta2, 0, 255)) + } + } +} + +func predFunc8VE(z *Decoder, y, x int) { + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = z.ybr[y-1][x+i] + } + } +} + +func predFunc8HE(z *Decoder, y, x int) { + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = z.ybr[y+j][x-1] + } + } +} + +func predFunc8DCTop(z *Decoder, y, x int) { + sum := uint32(4) + for j := 0; j < 8; j++ { + sum += uint32(z.ybr[y+j][x-1]) + } + avg := uint8(sum / 8) + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc8DCLeft(z *Decoder, y, x int) { + sum := uint32(4) + for i := 0; i < 8; i++ { + sum += uint32(z.ybr[y-1][x+i]) + } + avg := uint8(sum / 8) + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc8DCTopLeft(z *Decoder, y, x int) { + for j := 0; j < 8; j++ { + for i := 0; i < 8; i++ { + z.ybr[y+j][x+i] = 0x80 + } + } +} + +func predFunc16DC(z *Decoder, y, x int) { + sum := uint32(16) + for i := 0; i < 16; i++ { + sum += uint32(z.ybr[y-1][x+i]) + } + for j := 0; j < 16; j++ { + sum += uint32(z.ybr[y+j][x-1]) + } + avg := uint8(sum / 32) + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc16TM(z *Decoder, y, x int) { + delta0 := -int32(z.ybr[y-1][x-1]) + for j := 0; j < 16; j++ { + delta1 := delta0 + int32(z.ybr[y+j][x-1]) + for i := 0; i < 16; i++ { + delta2 := delta1 + int32(z.ybr[y-1][x+i]) + z.ybr[y+j][x+i] = uint8(clip(delta2, 0, 255)) + } + } +} + +func predFunc16VE(z *Decoder, y, x int) { + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = z.ybr[y-1][x+i] + } + } +} + +func predFunc16HE(z *Decoder, y, x int) { + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = z.ybr[y+j][x-1] + } + } +} + +func predFunc16DCTop(z *Decoder, y, x int) { + sum := uint32(8) + for j := 0; j < 16; j++ { + sum += uint32(z.ybr[y+j][x-1]) + } + avg := uint8(sum / 16) + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc16DCLeft(z *Decoder, y, x int) { + sum := uint32(8) + for i := 0; i < 16; i++ { + sum += uint32(z.ybr[y-1][x+i]) + } + avg := uint8(sum / 16) + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = avg + } + } +} + +func predFunc16DCTopLeft(z *Decoder, y, x int) { + for j := 0; j < 16; j++ { + for i := 0; i < 16; i++ { + z.ybr[y+j][x+i] = 0x80 + } + } +} diff --git a/vendor/golang.org/x/image/vp8/quant.go b/vendor/golang.org/x/image/vp8/quant.go new file mode 100644 index 0000000..da43616 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/quant.go @@ -0,0 +1,98 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file implements parsing the quantization factors. + +// quant are DC/AC quantization factors. +type quant struct { + y1 [2]uint16 + y2 [2]uint16 + uv [2]uint16 +} + +// clip clips x to the range [min, max] inclusive. +func clip(x, min, max int32) int32 { + if x < min { + return min + } + if x > max { + return max + } + return x +} + +// parseQuant parses the quantization factors, as specified in section 9.6. +func (d *Decoder) parseQuant() { + baseQ0 := d.fp.readUint(uniformProb, 7) + dqy1DC := d.fp.readOptionalInt(uniformProb, 4) + const dqy1AC = 0 + dqy2DC := d.fp.readOptionalInt(uniformProb, 4) + dqy2AC := d.fp.readOptionalInt(uniformProb, 4) + dquvDC := d.fp.readOptionalInt(uniformProb, 4) + dquvAC := d.fp.readOptionalInt(uniformProb, 4) + for i := 0; i < nSegment; i++ { + q := int32(baseQ0) + if d.segmentHeader.useSegment { + if d.segmentHeader.relativeDelta { + q += int32(d.segmentHeader.quantizer[i]) + } else { + q = int32(d.segmentHeader.quantizer[i]) + } + } + d.quant[i].y1[0] = dequantTableDC[clip(q+dqy1DC, 0, 127)] + d.quant[i].y1[1] = dequantTableAC[clip(q+dqy1AC, 0, 127)] + d.quant[i].y2[0] = dequantTableDC[clip(q+dqy2DC, 0, 127)] * 2 + d.quant[i].y2[1] = dequantTableAC[clip(q+dqy2AC, 0, 127)] * 155 / 100 + if d.quant[i].y2[1] < 8 { + d.quant[i].y2[1] = 8 + } + // The 117 is not a typo. The dequant_init function in the spec's Reference + // Decoder Source Code (http://tools.ietf.org/html/rfc6386#section-9.6 Page 145) + // says to clamp the LHS value at 132, which is equal to dequantTableDC[117]. + d.quant[i].uv[0] = dequantTableDC[clip(q+dquvDC, 0, 117)] + d.quant[i].uv[1] = dequantTableAC[clip(q+dquvAC, 0, 127)] + } +} + +// The dequantization tables are specified in section 14.1. +var ( + dequantTableDC = [128]uint16{ + 4, 5, 6, 7, 8, 9, 10, 10, + 11, 12, 13, 14, 15, 16, 17, 17, + 18, 19, 20, 20, 21, 21, 22, 22, + 23, 23, 24, 25, 25, 26, 27, 28, + 29, 30, 31, 32, 33, 34, 35, 36, + 37, 37, 38, 39, 40, 41, 42, 43, + 44, 45, 46, 46, 47, 48, 49, 50, + 51, 52, 53, 54, 55, 56, 57, 58, + 59, 60, 61, 62, 63, 64, 65, 66, + 67, 68, 69, 70, 71, 72, 73, 74, + 75, 76, 76, 77, 78, 79, 80, 81, + 82, 83, 84, 85, 86, 87, 88, 89, + 91, 93, 95, 96, 98, 100, 101, 102, + 104, 106, 108, 110, 112, 114, 116, 118, + 122, 124, 126, 128, 130, 132, 134, 136, + 138, 140, 143, 145, 148, 151, 154, 157, + } + dequantTableAC = [128]uint16{ + 4, 5, 6, 7, 8, 9, 10, 11, + 12, 13, 14, 15, 16, 17, 18, 19, + 20, 21, 22, 23, 24, 25, 26, 27, + 28, 29, 30, 31, 32, 33, 34, 35, + 36, 37, 38, 39, 40, 41, 42, 43, + 44, 45, 46, 47, 48, 49, 50, 51, + 52, 53, 54, 55, 56, 57, 58, 60, + 62, 64, 66, 68, 70, 72, 74, 76, + 78, 80, 82, 84, 86, 88, 90, 92, + 94, 96, 98, 100, 102, 104, 106, 108, + 110, 112, 114, 116, 119, 122, 125, 128, + 131, 134, 137, 140, 143, 146, 149, 152, + 155, 158, 161, 164, 167, 170, 173, 177, + 181, 185, 189, 193, 197, 201, 205, 209, + 213, 217, 221, 225, 229, 234, 239, 245, + 249, 254, 259, 264, 269, 274, 279, 284, + } +) diff --git a/vendor/golang.org/x/image/vp8/reconstruct.go b/vendor/golang.org/x/image/vp8/reconstruct.go new file mode 100644 index 0000000..c1cc4b5 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/reconstruct.go @@ -0,0 +1,442 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file implements decoding DCT/WHT residual coefficients and +// reconstructing YCbCr data equal to predicted values plus residuals. +// +// There are 1*16*16 + 2*8*8 + 1*4*4 coefficients per macroblock: +// - 1*16*16 luma DCT coefficients, +// - 2*8*8 chroma DCT coefficients, and +// - 1*4*4 luma WHT coefficients. +// Coefficients are read in lots of 16, and the later coefficients in each lot +// are often zero. +// +// The YCbCr data consists of 1*16*16 luma values and 2*8*8 chroma values, +// plus previously decoded values along the top and left borders. The combined +// values are laid out as a [1+16+1+8][32]uint8 so that vertically adjacent +// samples are 32 bytes apart. In detail, the layout is: +// +// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +// . . . . . . . a b b b b b b b b b b b b b b b b c c c c . . . . 0 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 1 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 2 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 3 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y c c c c . . . . 4 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 5 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 6 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 7 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y c c c c . . . . 8 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 9 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 10 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 11 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y c c c c . . . . 12 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 13 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 14 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 15 +// . . . . . . . d Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y . . . . . . . . 16 +// . . . . . . . e f f f f f f f f . . . . . . . g h h h h h h h h 17 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 18 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 19 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 20 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 21 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 22 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 23 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 24 +// . . . . . . . i B B B B B B B B . . . . . . . j R R R R R R R R 25 +// +// Y, B and R are the reconstructed luma (Y) and chroma (B, R) values. +// The Y values are predicted (either as one 16x16 region or 16 4x4 regions) +// based on the row above's Y values (some combination of {abc} or {dYC}) and +// the column left's Y values (either {ad} or {bY}). Similarly, B and R values +// are predicted on the row above and column left of their respective 8x8 +// region: {efi} for B, {ghj} for R. +// +// For uppermost macroblocks (i.e. those with mby == 0), the {abcefgh} values +// are initialized to 0x81. Otherwise, they are copied from the bottom row of +// the macroblock above. The {c} values are then duplicated from row 0 to rows +// 4, 8 and 12 of the ybr workspace. +// Similarly, for leftmost macroblocks (i.e. those with mbx == 0), the {adeigj} +// values are initialized to 0x7f. Otherwise, they are copied from the right +// column of the macroblock to the left. +// For the top-left macroblock (with mby == 0 && mbx == 0), {aeg} is 0x81. +// +// When moving from one macroblock to the next horizontally, the {adeigj} +// values can simply be copied from the workspace to itself, shifted by 8 or +// 16 columns. When moving from one macroblock to the next vertically, +// filtering can occur and hence the row values have to be copied from the +// post-filtered image instead of the pre-filtered workspace. + +const ( + bCoeffBase = 1*16*16 + 0*8*8 + rCoeffBase = 1*16*16 + 1*8*8 + whtCoeffBase = 1*16*16 + 2*8*8 +) + +const ( + ybrYX = 8 + ybrYY = 1 + ybrBX = 8 + ybrBY = 18 + ybrRX = 24 + ybrRY = 18 +) + +// prepareYBR prepares the {abcdefghij} elements of ybr. +func (d *Decoder) prepareYBR(mbx, mby int) { + if mbx == 0 { + for y := 0; y < 17; y++ { + d.ybr[y][7] = 0x81 + } + for y := 17; y < 26; y++ { + d.ybr[y][7] = 0x81 + d.ybr[y][23] = 0x81 + } + } else { + for y := 0; y < 17; y++ { + d.ybr[y][7] = d.ybr[y][7+16] + } + for y := 17; y < 26; y++ { + d.ybr[y][7] = d.ybr[y][15] + d.ybr[y][23] = d.ybr[y][31] + } + } + if mby == 0 { + for x := 7; x < 28; x++ { + d.ybr[0][x] = 0x7f + } + for x := 7; x < 16; x++ { + d.ybr[17][x] = 0x7f + } + for x := 23; x < 32; x++ { + d.ybr[17][x] = 0x7f + } + } else { + for i := 0; i < 16; i++ { + d.ybr[0][8+i] = d.img.Y[(16*mby-1)*d.img.YStride+16*mbx+i] + } + for i := 0; i < 8; i++ { + d.ybr[17][8+i] = d.img.Cb[(8*mby-1)*d.img.CStride+8*mbx+i] + } + for i := 0; i < 8; i++ { + d.ybr[17][24+i] = d.img.Cr[(8*mby-1)*d.img.CStride+8*mbx+i] + } + if mbx == d.mbw-1 { + for i := 16; i < 20; i++ { + d.ybr[0][8+i] = d.img.Y[(16*mby-1)*d.img.YStride+16*mbx+15] + } + } else { + for i := 16; i < 20; i++ { + d.ybr[0][8+i] = d.img.Y[(16*mby-1)*d.img.YStride+16*mbx+i] + } + } + } + for y := 4; y < 16; y += 4 { + d.ybr[y][24] = d.ybr[0][24] + d.ybr[y][25] = d.ybr[0][25] + d.ybr[y][26] = d.ybr[0][26] + d.ybr[y][27] = d.ybr[0][27] + } +} + +// btou converts a bool to a 0/1 value. +func btou(b bool) uint8 { + if b { + return 1 + } + return 0 +} + +// pack packs four 0/1 values into four bits of a uint32. +func pack(x [4]uint8, shift int) uint32 { + u := uint32(x[0])<<0 | uint32(x[1])<<1 | uint32(x[2])<<2 | uint32(x[3])<<3 + return u << uint(shift) +} + +// unpack unpacks four 0/1 values from a four-bit value. +var unpack = [16][4]uint8{ + {0, 0, 0, 0}, + {1, 0, 0, 0}, + {0, 1, 0, 0}, + {1, 1, 0, 0}, + {0, 0, 1, 0}, + {1, 0, 1, 0}, + {0, 1, 1, 0}, + {1, 1, 1, 0}, + {0, 0, 0, 1}, + {1, 0, 0, 1}, + {0, 1, 0, 1}, + {1, 1, 0, 1}, + {0, 0, 1, 1}, + {1, 0, 1, 1}, + {0, 1, 1, 1}, + {1, 1, 1, 1}, +} + +var ( + // The mapping from 4x4 region position to band is specified in section 13.3. + bands = [17]uint8{0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7, 0} + // Category probabilties are specified in section 13.2. + // Decoding categories 1 and 2 are done inline. + cat3456 = [4][12]uint8{ + {173, 148, 140, 0, 0, 0, 0, 0, 0, 0, 0, 0}, + {176, 155, 140, 135, 0, 0, 0, 0, 0, 0, 0, 0}, + {180, 157, 141, 134, 130, 0, 0, 0, 0, 0, 0, 0}, + {254, 254, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0}, + } + // The zigzag order is: + // 0 1 5 6 + // 2 4 7 12 + // 3 8 11 13 + // 9 10 14 15 + zigzag = [16]uint8{0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15} +) + +// parseResiduals4 parses a 4x4 region of residual coefficients, as specified +// in section 13.3, and returns a 0/1 value indicating whether there was at +// least one non-zero coefficient. +// r is the partition to read bits from. +// plane and context describe which token probability table to use. context is +// either 0, 1 or 2, and equals how many of the macroblock left and macroblock +// above have non-zero coefficients. +// quant are the DC/AC quantization factors. +// skipFirstCoeff is whether the DC coefficient has already been parsed. +// coeffBase is the base index of d.coeff to write to. +func (d *Decoder) parseResiduals4(r *partition, plane int, context uint8, quant [2]uint16, skipFirstCoeff bool, coeffBase int) uint8 { + prob, n := &d.tokenProb[plane], 0 + if skipFirstCoeff { + n = 1 + } + p := prob[bands[n]][context] + if !r.readBit(p[0]) { + return 0 + } + for n != 16 { + n++ + if !r.readBit(p[1]) { + p = prob[bands[n]][0] + continue + } + var v uint32 + if !r.readBit(p[2]) { + v = 1 + p = prob[bands[n]][1] + } else { + if !r.readBit(p[3]) { + if !r.readBit(p[4]) { + v = 2 + } else { + v = 3 + r.readUint(p[5], 1) + } + } else if !r.readBit(p[6]) { + if !r.readBit(p[7]) { + // Category 1. + v = 5 + r.readUint(159, 1) + } else { + // Category 2. + v = 7 + 2*r.readUint(165, 1) + r.readUint(145, 1) + } + } else { + // Categories 3, 4, 5 or 6. + b1 := r.readUint(p[8], 1) + b0 := r.readUint(p[9+b1], 1) + cat := 2*b1 + b0 + tab := &cat3456[cat] + v = 0 + for i := 0; tab[i] != 0; i++ { + v *= 2 + v += r.readUint(tab[i], 1) + } + v += 3 + (8 << cat) + } + p = prob[bands[n]][2] + } + z := zigzag[n-1] + c := int32(v) * int32(quant[btou(z > 0)]) + if r.readBit(uniformProb) { + c = -c + } + d.coeff[coeffBase+int(z)] = int16(c) + if n == 16 || !r.readBit(p[0]) { + return 1 + } + } + return 1 +} + +// parseResiduals parses the residuals and returns whether inner loop filtering +// should be skipped for this macroblock. +func (d *Decoder) parseResiduals(mbx, mby int) (skip bool) { + partition := &d.op[mby&(d.nOP-1)] + plane := planeY1SansY2 + quant := &d.quant[d.segment] + + // Parse the DC coefficient of each 4x4 luma region. + if d.usePredY16 { + nz := d.parseResiduals4(partition, planeY2, d.leftMB.nzY16+d.upMB[mbx].nzY16, quant.y2, false, whtCoeffBase) + d.leftMB.nzY16 = nz + d.upMB[mbx].nzY16 = nz + d.inverseWHT16() + plane = planeY1WithY2 + } + + var ( + nzDC, nzAC [4]uint8 + nzDCMask, nzACMask uint32 + coeffBase int + ) + + // Parse the luma coefficients. + lnz := unpack[d.leftMB.nzMask&0x0f] + unz := unpack[d.upMB[mbx].nzMask&0x0f] + for y := 0; y < 4; y++ { + nz := lnz[y] + for x := 0; x < 4; x++ { + nz = d.parseResiduals4(partition, plane, nz+unz[x], quant.y1, d.usePredY16, coeffBase) + unz[x] = nz + nzAC[x] = nz + nzDC[x] = btou(d.coeff[coeffBase] != 0) + coeffBase += 16 + } + lnz[y] = nz + nzDCMask |= pack(nzDC, y*4) + nzACMask |= pack(nzAC, y*4) + } + lnzMask := pack(lnz, 0) + unzMask := pack(unz, 0) + + // Parse the chroma coefficients. + lnz = unpack[d.leftMB.nzMask>>4] + unz = unpack[d.upMB[mbx].nzMask>>4] + for c := 0; c < 4; c += 2 { + for y := 0; y < 2; y++ { + nz := lnz[y+c] + for x := 0; x < 2; x++ { + nz = d.parseResiduals4(partition, planeUV, nz+unz[x+c], quant.uv, false, coeffBase) + unz[x+c] = nz + nzAC[y*2+x] = nz + nzDC[y*2+x] = btou(d.coeff[coeffBase] != 0) + coeffBase += 16 + } + lnz[y+c] = nz + } + nzDCMask |= pack(nzDC, 16+c*2) + nzACMask |= pack(nzAC, 16+c*2) + } + lnzMask |= pack(lnz, 4) + unzMask |= pack(unz, 4) + + // Save decoder state. + d.leftMB.nzMask = uint8(lnzMask) + d.upMB[mbx].nzMask = uint8(unzMask) + d.nzDCMask = nzDCMask + d.nzACMask = nzACMask + + // Section 15.1 of the spec says that "Steps 2 and 4 [of the loop filter] + // are skipped... [if] there is no DCT coefficient coded for the whole + // macroblock." + return nzDCMask == 0 && nzACMask == 0 +} + +// reconstructMacroblock applies the predictor functions and adds the inverse- +// DCT transformed residuals to recover the YCbCr data. +func (d *Decoder) reconstructMacroblock(mbx, mby int) { + if d.usePredY16 { + p := checkTopLeftPred(mbx, mby, d.predY16) + predFunc16[p](d, 1, 8) + for j := 0; j < 4; j++ { + for i := 0; i < 4; i++ { + n := 4*j + i + y := 4*j + 1 + x := 4*i + 8 + mask := uint32(1) << uint(n) + if d.nzACMask&mask != 0 { + d.inverseDCT4(y, x, 16*n) + } else if d.nzDCMask&mask != 0 { + d.inverseDCT4DCOnly(y, x, 16*n) + } + } + } + } else { + for j := 0; j < 4; j++ { + for i := 0; i < 4; i++ { + n := 4*j + i + y := 4*j + 1 + x := 4*i + 8 + predFunc4[d.predY4[j][i]](d, y, x) + mask := uint32(1) << uint(n) + if d.nzACMask&mask != 0 { + d.inverseDCT4(y, x, 16*n) + } else if d.nzDCMask&mask != 0 { + d.inverseDCT4DCOnly(y, x, 16*n) + } + } + } + } + p := checkTopLeftPred(mbx, mby, d.predC8) + predFunc8[p](d, ybrBY, ybrBX) + if d.nzACMask&0x0f0000 != 0 { + d.inverseDCT8(ybrBY, ybrBX, bCoeffBase) + } else if d.nzDCMask&0x0f0000 != 0 { + d.inverseDCT8DCOnly(ybrBY, ybrBX, bCoeffBase) + } + predFunc8[p](d, ybrRY, ybrRX) + if d.nzACMask&0xf00000 != 0 { + d.inverseDCT8(ybrRY, ybrRX, rCoeffBase) + } else if d.nzDCMask&0xf00000 != 0 { + d.inverseDCT8DCOnly(ybrRY, ybrRX, rCoeffBase) + } +} + +// reconstruct reconstructs one macroblock and returns whether inner loop +// filtering should be skipped for it. +func (d *Decoder) reconstruct(mbx, mby int) (skip bool) { + if d.segmentHeader.updateMap { + if !d.fp.readBit(d.segmentHeader.prob[0]) { + d.segment = int(d.fp.readUint(d.segmentHeader.prob[1], 1)) + } else { + d.segment = int(d.fp.readUint(d.segmentHeader.prob[2], 1)) + 2 + } + } + if d.useSkipProb { + skip = d.fp.readBit(d.skipProb) + } + // Prepare the workspace. + for i := range d.coeff { + d.coeff[i] = 0 + } + d.prepareYBR(mbx, mby) + // Parse the predictor modes. + d.usePredY16 = d.fp.readBit(145) + if d.usePredY16 { + d.parsePredModeY16(mbx) + } else { + d.parsePredModeY4(mbx) + } + d.parsePredModeC8() + // Parse the residuals. + if !skip { + skip = d.parseResiduals(mbx, mby) + } else { + if d.usePredY16 { + d.leftMB.nzY16 = 0 + d.upMB[mbx].nzY16 = 0 + } + d.leftMB.nzMask = 0 + d.upMB[mbx].nzMask = 0 + d.nzDCMask = 0 + d.nzACMask = 0 + } + // Reconstruct the YCbCr data and copy it to the image. + d.reconstructMacroblock(mbx, mby) + for i, y := (mby*d.img.YStride+mbx)*16, 0; y < 16; i, y = i+d.img.YStride, y+1 { + copy(d.img.Y[i:i+16], d.ybr[ybrYY+y][ybrYX:ybrYX+16]) + } + for i, y := (mby*d.img.CStride+mbx)*8, 0; y < 8; i, y = i+d.img.CStride, y+1 { + copy(d.img.Cb[i:i+8], d.ybr[ybrBY+y][ybrBX:ybrBX+8]) + copy(d.img.Cr[i:i+8], d.ybr[ybrRY+y][ybrRX:ybrRX+8]) + } + return skip +} diff --git a/vendor/golang.org/x/image/vp8/token.go b/vendor/golang.org/x/image/vp8/token.go new file mode 100644 index 0000000..da99cf0 --- /dev/null +++ b/vendor/golang.org/x/image/vp8/token.go @@ -0,0 +1,381 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package vp8 + +// This file contains token probabilities for decoding DCT/WHT coefficients, as +// specified in chapter 13. + +func (d *Decoder) parseTokenProb() { + for i := range d.tokenProb { + for j := range d.tokenProb[i] { + for k := range d.tokenProb[i][j] { + for l := range d.tokenProb[i][j][k] { + if d.fp.readBit(tokenProbUpdateProb[i][j][k][l]) { + d.tokenProb[i][j][k][l] = uint8(d.fp.readUint(uniformProb, 8)) + } + } + } + } + } +} + +// The plane enumeration is specified in section 13.3. +const ( + planeY1WithY2 = iota + planeY2 + planeUV + planeY1SansY2 + nPlane +) + +const ( + nBand = 8 + nContext = 3 + nProb = 11 +) + +// Token probability update probabilities are specified in section 13.4. +var tokenProbUpdateProb = [nPlane][nBand][nContext][nProb]uint8{ + { + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {176, 246, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {223, 241, 252, 255, 255, 255, 255, 255, 255, 255, 255}, + {249, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 244, 252, 255, 255, 255, 255, 255, 255, 255, 255}, + {234, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 246, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {239, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {251, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {251, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 253, 255, 254, 255, 255, 255, 255, 255, 255}, + {250, 255, 254, 255, 254, 255, 255, 255, 255, 255, 255}, + {254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + }, + { + { + {217, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {225, 252, 241, 253, 255, 255, 254, 255, 255, 255, 255}, + {234, 250, 241, 250, 253, 255, 253, 254, 255, 255, 255}, + }, + { + {255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {223, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {238, 253, 254, 254, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {249, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 253, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {247, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {252, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + }, + { + { + {186, 251, 250, 255, 255, 255, 255, 255, 255, 255, 255}, + {234, 251, 244, 254, 255, 255, 255, 255, 255, 255, 255}, + {251, 251, 243, 253, 254, 255, 254, 255, 255, 255, 255}, + }, + { + {255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {236, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {251, 253, 253, 254, 254, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + }, + { + { + {248, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {250, 254, 252, 254, 255, 255, 255, 255, 255, 255, 255}, + {248, 254, 249, 253, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {246, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {252, 254, 251, 254, 254, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 254, 252, 255, 255, 255, 255, 255, 255, 255, 255}, + {248, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {253, 255, 254, 254, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {245, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {253, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 251, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {252, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 252, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {249, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 253, 255, 255, 255, 255, 255, 255, 255, 255}, + {250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + { + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + {255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255}, + }, + }, +} + +// Default token probabilities are specified in section 13.5. +var defaultTokenProb = [nPlane][nBand][nContext][nProb]uint8{ + { + { + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + { + {253, 136, 254, 255, 228, 219, 128, 128, 128, 128, 128}, + {189, 129, 242, 255, 227, 213, 255, 219, 128, 128, 128}, + {106, 126, 227, 252, 214, 209, 255, 255, 128, 128, 128}, + }, + { + {1, 98, 248, 255, 236, 226, 255, 255, 128, 128, 128}, + {181, 133, 238, 254, 221, 234, 255, 154, 128, 128, 128}, + {78, 134, 202, 247, 198, 180, 255, 219, 128, 128, 128}, + }, + { + {1, 185, 249, 255, 243, 255, 128, 128, 128, 128, 128}, + {184, 150, 247, 255, 236, 224, 128, 128, 128, 128, 128}, + {77, 110, 216, 255, 236, 230, 128, 128, 128, 128, 128}, + }, + { + {1, 101, 251, 255, 241, 255, 128, 128, 128, 128, 128}, + {170, 139, 241, 252, 236, 209, 255, 255, 128, 128, 128}, + {37, 116, 196, 243, 228, 255, 255, 255, 128, 128, 128}, + }, + { + {1, 204, 254, 255, 245, 255, 128, 128, 128, 128, 128}, + {207, 160, 250, 255, 238, 128, 128, 128, 128, 128, 128}, + {102, 103, 231, 255, 211, 171, 128, 128, 128, 128, 128}, + }, + { + {1, 152, 252, 255, 240, 255, 128, 128, 128, 128, 128}, + {177, 135, 243, 255, 234, 225, 128, 128, 128, 128, 128}, + {80, 129, 211, 255, 194, 224, 128, 128, 128, 128, 128}, + }, + { + {1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {246, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {255, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + }, + { + { + {198, 35, 237, 223, 193, 187, 162, 160, 145, 155, 62}, + {131, 45, 198, 221, 172, 176, 220, 157, 252, 221, 1}, + {68, 47, 146, 208, 149, 167, 221, 162, 255, 223, 128}, + }, + { + {1, 149, 241, 255, 221, 224, 255, 255, 128, 128, 128}, + {184, 141, 234, 253, 222, 220, 255, 199, 128, 128, 128}, + {81, 99, 181, 242, 176, 190, 249, 202, 255, 255, 128}, + }, + { + {1, 129, 232, 253, 214, 197, 242, 196, 255, 255, 128}, + {99, 121, 210, 250, 201, 198, 255, 202, 128, 128, 128}, + {23, 91, 163, 242, 170, 187, 247, 210, 255, 255, 128}, + }, + { + {1, 200, 246, 255, 234, 255, 128, 128, 128, 128, 128}, + {109, 178, 241, 255, 231, 245, 255, 255, 128, 128, 128}, + {44, 130, 201, 253, 205, 192, 255, 255, 128, 128, 128}, + }, + { + {1, 132, 239, 251, 219, 209, 255, 165, 128, 128, 128}, + {94, 136, 225, 251, 218, 190, 255, 255, 128, 128, 128}, + {22, 100, 174, 245, 186, 161, 255, 199, 128, 128, 128}, + }, + { + {1, 182, 249, 255, 232, 235, 128, 128, 128, 128, 128}, + {124, 143, 241, 255, 227, 234, 128, 128, 128, 128, 128}, + {35, 77, 181, 251, 193, 211, 255, 205, 128, 128, 128}, + }, + { + {1, 157, 247, 255, 236, 231, 255, 255, 128, 128, 128}, + {121, 141, 235, 255, 225, 227, 255, 255, 128, 128, 128}, + {45, 99, 188, 251, 195, 217, 255, 224, 128, 128, 128}, + }, + { + {1, 1, 251, 255, 213, 255, 128, 128, 128, 128, 128}, + {203, 1, 248, 255, 255, 128, 128, 128, 128, 128, 128}, + {137, 1, 177, 255, 224, 255, 128, 128, 128, 128, 128}, + }, + }, + { + { + {253, 9, 248, 251, 207, 208, 255, 192, 128, 128, 128}, + {175, 13, 224, 243, 193, 185, 249, 198, 255, 255, 128}, + {73, 17, 171, 221, 161, 179, 236, 167, 255, 234, 128}, + }, + { + {1, 95, 247, 253, 212, 183, 255, 255, 128, 128, 128}, + {239, 90, 244, 250, 211, 209, 255, 255, 128, 128, 128}, + {155, 77, 195, 248, 188, 195, 255, 255, 128, 128, 128}, + }, + { + {1, 24, 239, 251, 218, 219, 255, 205, 128, 128, 128}, + {201, 51, 219, 255, 196, 186, 128, 128, 128, 128, 128}, + {69, 46, 190, 239, 201, 218, 255, 228, 128, 128, 128}, + }, + { + {1, 191, 251, 255, 255, 128, 128, 128, 128, 128, 128}, + {223, 165, 249, 255, 213, 255, 128, 128, 128, 128, 128}, + {141, 124, 248, 255, 255, 128, 128, 128, 128, 128, 128}, + }, + { + {1, 16, 248, 255, 255, 128, 128, 128, 128, 128, 128}, + {190, 36, 230, 255, 236, 255, 128, 128, 128, 128, 128}, + {149, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + { + {1, 226, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {247, 192, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {240, 128, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + { + {1, 134, 252, 255, 255, 128, 128, 128, 128, 128, 128}, + {213, 62, 250, 255, 255, 128, 128, 128, 128, 128, 128}, + {55, 93, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + { + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + {128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + }, + { + { + {202, 24, 213, 235, 186, 191, 220, 160, 240, 175, 255}, + {126, 38, 182, 232, 169, 184, 228, 174, 255, 187, 128}, + {61, 46, 138, 219, 151, 178, 240, 170, 255, 216, 128}, + }, + { + {1, 112, 230, 250, 199, 191, 247, 159, 255, 255, 128}, + {166, 109, 228, 252, 211, 215, 255, 174, 128, 128, 128}, + {39, 77, 162, 232, 172, 180, 245, 178, 255, 255, 128}, + }, + { + {1, 52, 220, 246, 198, 199, 249, 220, 255, 255, 128}, + {124, 74, 191, 243, 183, 193, 250, 221, 255, 255, 128}, + {24, 71, 130, 219, 154, 170, 243, 182, 255, 255, 128}, + }, + { + {1, 182, 225, 249, 219, 240, 255, 224, 128, 128, 128}, + {149, 150, 226, 252, 216, 205, 255, 171, 128, 128, 128}, + {28, 108, 170, 242, 183, 194, 254, 223, 255, 255, 128}, + }, + { + {1, 81, 230, 252, 204, 203, 255, 192, 128, 128, 128}, + {123, 102, 209, 247, 188, 196, 255, 233, 128, 128, 128}, + {20, 95, 153, 243, 164, 173, 255, 203, 128, 128, 128}, + }, + { + {1, 222, 248, 255, 216, 213, 128, 128, 128, 128, 128}, + {168, 175, 246, 252, 235, 205, 255, 255, 128, 128, 128}, + {47, 116, 215, 255, 211, 212, 255, 255, 128, 128, 128}, + }, + { + {1, 121, 236, 253, 212, 214, 255, 255, 128, 128, 128}, + {141, 84, 213, 252, 201, 202, 255, 219, 128, 128, 128}, + {42, 80, 160, 240, 162, 185, 255, 205, 128, 128, 128}, + }, + { + {1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {244, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + {238, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128}, + }, + }, +} -- cgit v1.2.3