457 lines
14 KiB
C
457 lines
14 KiB
C
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// Copyright 2011 Google Inc. All Rights Reserved.
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//
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// Use of this source code is governed by a BSD-style license
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// that can be found in the COPYING file in the root of the source
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// tree. An additional intellectual property rights grant can be found
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// in the file PATENTS. All contributing project authors may
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// be found in the AUTHORS file in the root of the source tree.
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// -----------------------------------------------------------------------------
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//
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// VP8Iterator: block iterator
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//
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// Author: Skal (pascal.massimino@gmail.com)
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#include <string.h>
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#include "./vp8enci.h"
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//------------------------------------------------------------------------------
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// VP8Iterator
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//------------------------------------------------------------------------------
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static void InitLeft(VP8EncIterator* const it) {
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it->y_left_[-1] = it->u_left_[-1] = it->v_left_[-1] =
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(it->y_ > 0) ? 129 : 127;
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memset(it->y_left_, 129, 16);
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memset(it->u_left_, 129, 8);
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memset(it->v_left_, 129, 8);
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it->left_nz_[8] = 0;
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}
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static void InitTop(VP8EncIterator* const it) {
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const VP8Encoder* const enc = it->enc_;
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const size_t top_size = enc->mb_w_ * 16;
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memset(enc->y_top_, 127, 2 * top_size);
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memset(enc->nz_, 0, enc->mb_w_ * sizeof(*enc->nz_));
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}
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void VP8IteratorSetRow(VP8EncIterator* const it, int y) {
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VP8Encoder* const enc = it->enc_;
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it->x_ = 0;
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it->y_ = y;
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it->bw_ = &enc->parts_[y & (enc->num_parts_ - 1)];
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it->preds_ = enc->preds_ + y * 4 * enc->preds_w_;
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it->nz_ = enc->nz_;
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it->mb_ = enc->mb_info_ + y * enc->mb_w_;
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it->y_top_ = enc->y_top_;
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it->uv_top_ = enc->uv_top_;
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InitLeft(it);
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}
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void VP8IteratorReset(VP8EncIterator* const it) {
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VP8Encoder* const enc = it->enc_;
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VP8IteratorSetRow(it, 0);
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VP8IteratorSetCountDown(it, enc->mb_w_ * enc->mb_h_); // default
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InitTop(it);
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InitLeft(it);
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memset(it->bit_count_, 0, sizeof(it->bit_count_));
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it->do_trellis_ = 0;
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}
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void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down) {
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it->count_down_ = it->count_down0_ = count_down;
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}
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int VP8IteratorIsDone(const VP8EncIterator* const it) {
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return (it->count_down_ <= 0);
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}
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void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it) {
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it->enc_ = enc;
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it->y_stride_ = enc->pic_->y_stride;
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it->uv_stride_ = enc->pic_->uv_stride;
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it->yuv_in_ = (uint8_t*)DO_ALIGN(it->yuv_mem_);
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it->yuv_out_ = it->yuv_in_ + YUV_SIZE;
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it->yuv_out2_ = it->yuv_out_ + YUV_SIZE;
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it->yuv_p_ = it->yuv_out2_ + YUV_SIZE;
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it->lf_stats_ = enc->lf_stats_;
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it->percent0_ = enc->percent_;
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it->y_left_ = (uint8_t*)DO_ALIGN(it->yuv_left_mem_ + 1);
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it->u_left_ = it->y_left_ + 16 + 16;
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it->v_left_ = it->u_left_ + 16;
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VP8IteratorReset(it);
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}
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int VP8IteratorProgress(const VP8EncIterator* const it, int delta) {
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VP8Encoder* const enc = it->enc_;
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if (delta && enc->pic_->progress_hook != NULL) {
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const int done = it->count_down0_ - it->count_down_;
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const int percent = (it->count_down0_ <= 0)
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? it->percent0_
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: it->percent0_ + delta * done / it->count_down0_;
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return WebPReportProgress(enc->pic_, percent, &enc->percent_);
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}
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return 1;
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}
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//------------------------------------------------------------------------------
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// Import the source samples into the cache. Takes care of replicating
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// boundary pixels if necessary.
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static WEBP_INLINE int MinSize(int a, int b) { return (a < b) ? a : b; }
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static void ImportBlock(const uint8_t* src, int src_stride,
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uint8_t* dst, int w, int h, int size) {
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int i;
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for (i = 0; i < h; ++i) {
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memcpy(dst, src, w);
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if (w < size) {
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memset(dst + w, dst[w - 1], size - w);
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}
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dst += BPS;
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src += src_stride;
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}
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for (i = h; i < size; ++i) {
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memcpy(dst, dst - BPS, size);
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dst += BPS;
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}
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}
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static void ImportLine(const uint8_t* src, int src_stride,
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uint8_t* dst, int len, int total_len) {
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int i;
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for (i = 0; i < len; ++i, src += src_stride) dst[i] = *src;
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for (; i < total_len; ++i) dst[i] = dst[len - 1];
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}
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void VP8IteratorImport(VP8EncIterator* const it, uint8_t* tmp_32) {
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const VP8Encoder* const enc = it->enc_;
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const int x = it->x_, y = it->y_;
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const WebPPicture* const pic = enc->pic_;
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const uint8_t* const ysrc = pic->y + (y * pic->y_stride + x) * 16;
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const uint8_t* const usrc = pic->u + (y * pic->uv_stride + x) * 8;
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const uint8_t* const vsrc = pic->v + (y * pic->uv_stride + x) * 8;
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const int w = MinSize(pic->width - x * 16, 16);
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const int h = MinSize(pic->height - y * 16, 16);
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const int uv_w = (w + 1) >> 1;
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const int uv_h = (h + 1) >> 1;
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ImportBlock(ysrc, pic->y_stride, it->yuv_in_ + Y_OFF, w, h, 16);
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ImportBlock(usrc, pic->uv_stride, it->yuv_in_ + U_OFF, uv_w, uv_h, 8);
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ImportBlock(vsrc, pic->uv_stride, it->yuv_in_ + V_OFF, uv_w, uv_h, 8);
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if (tmp_32 == NULL) return;
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// Import source (uncompressed) samples into boundary.
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if (x == 0) {
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InitLeft(it);
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} else {
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if (y == 0) {
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it->y_left_[-1] = it->u_left_[-1] = it->v_left_[-1] = 127;
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} else {
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it->y_left_[-1] = ysrc[- 1 - pic->y_stride];
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it->u_left_[-1] = usrc[- 1 - pic->uv_stride];
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it->v_left_[-1] = vsrc[- 1 - pic->uv_stride];
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}
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ImportLine(ysrc - 1, pic->y_stride, it->y_left_, h, 16);
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ImportLine(usrc - 1, pic->uv_stride, it->u_left_, uv_h, 8);
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ImportLine(vsrc - 1, pic->uv_stride, it->v_left_, uv_h, 8);
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}
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it->y_top_ = tmp_32 + 0;
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it->uv_top_ = tmp_32 + 16;
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if (y == 0) {
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memset(tmp_32, 127, 32 * sizeof(*tmp_32));
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} else {
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ImportLine(ysrc - pic->y_stride, 1, tmp_32, w, 16);
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ImportLine(usrc - pic->uv_stride, 1, tmp_32 + 16, uv_w, 8);
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ImportLine(vsrc - pic->uv_stride, 1, tmp_32 + 16 + 8, uv_w, 8);
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}
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}
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//------------------------------------------------------------------------------
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// Copy back the compressed samples into user space if requested.
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static void ExportBlock(const uint8_t* src, uint8_t* dst, int dst_stride,
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int w, int h) {
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while (h-- > 0) {
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memcpy(dst, src, w);
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dst += dst_stride;
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src += BPS;
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}
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}
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void VP8IteratorExport(const VP8EncIterator* const it) {
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const VP8Encoder* const enc = it->enc_;
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if (enc->config_->show_compressed) {
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const int x = it->x_, y = it->y_;
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const uint8_t* const ysrc = it->yuv_out_ + Y_OFF;
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const uint8_t* const usrc = it->yuv_out_ + U_OFF;
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const uint8_t* const vsrc = it->yuv_out_ + V_OFF;
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const WebPPicture* const pic = enc->pic_;
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uint8_t* const ydst = pic->y + (y * pic->y_stride + x) * 16;
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uint8_t* const udst = pic->u + (y * pic->uv_stride + x) * 8;
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uint8_t* const vdst = pic->v + (y * pic->uv_stride + x) * 8;
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int w = (pic->width - x * 16);
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int h = (pic->height - y * 16);
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if (w > 16) w = 16;
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if (h > 16) h = 16;
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// Luma plane
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ExportBlock(ysrc, ydst, pic->y_stride, w, h);
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{ // U/V planes
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const int uv_w = (w + 1) >> 1;
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const int uv_h = (h + 1) >> 1;
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ExportBlock(usrc, udst, pic->uv_stride, uv_w, uv_h);
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ExportBlock(vsrc, vdst, pic->uv_stride, uv_w, uv_h);
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}
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}
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}
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//------------------------------------------------------------------------------
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// Non-zero contexts setup/teardown
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// Nz bits:
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// 0 1 2 3 Y
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// 4 5 6 7
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// 8 9 10 11
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// 12 13 14 15
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// 16 17 U
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// 18 19
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// 20 21 V
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// 22 23
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// 24 DC-intra16
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// Convert packed context to byte array
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#define BIT(nz, n) (!!((nz) & (1 << (n))))
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void VP8IteratorNzToBytes(VP8EncIterator* const it) {
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const int tnz = it->nz_[0], lnz = it->nz_[-1];
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int* const top_nz = it->top_nz_;
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int* const left_nz = it->left_nz_;
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// Top-Y
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top_nz[0] = BIT(tnz, 12);
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top_nz[1] = BIT(tnz, 13);
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top_nz[2] = BIT(tnz, 14);
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top_nz[3] = BIT(tnz, 15);
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// Top-U
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top_nz[4] = BIT(tnz, 18);
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top_nz[5] = BIT(tnz, 19);
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// Top-V
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top_nz[6] = BIT(tnz, 22);
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top_nz[7] = BIT(tnz, 23);
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// DC
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top_nz[8] = BIT(tnz, 24);
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// left-Y
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left_nz[0] = BIT(lnz, 3);
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left_nz[1] = BIT(lnz, 7);
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left_nz[2] = BIT(lnz, 11);
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left_nz[3] = BIT(lnz, 15);
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// left-U
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left_nz[4] = BIT(lnz, 17);
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left_nz[5] = BIT(lnz, 19);
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// left-V
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left_nz[6] = BIT(lnz, 21);
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left_nz[7] = BIT(lnz, 23);
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// left-DC is special, iterated separately
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}
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void VP8IteratorBytesToNz(VP8EncIterator* const it) {
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uint32_t nz = 0;
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const int* const top_nz = it->top_nz_;
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const int* const left_nz = it->left_nz_;
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// top
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nz |= (top_nz[0] << 12) | (top_nz[1] << 13);
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nz |= (top_nz[2] << 14) | (top_nz[3] << 15);
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nz |= (top_nz[4] << 18) | (top_nz[5] << 19);
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nz |= (top_nz[6] << 22) | (top_nz[7] << 23);
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nz |= (top_nz[8] << 24); // we propagate the _top_ bit, esp. for intra4
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// left
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nz |= (left_nz[0] << 3) | (left_nz[1] << 7);
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nz |= (left_nz[2] << 11);
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nz |= (left_nz[4] << 17) | (left_nz[6] << 21);
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*it->nz_ = nz;
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}
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#undef BIT
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//------------------------------------------------------------------------------
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// Advance to the next position, doing the bookkeeping.
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void VP8IteratorSaveBoundary(VP8EncIterator* const it) {
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VP8Encoder* const enc = it->enc_;
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const int x = it->x_, y = it->y_;
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const uint8_t* const ysrc = it->yuv_out_ + Y_OFF;
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const uint8_t* const uvsrc = it->yuv_out_ + U_OFF;
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if (x < enc->mb_w_ - 1) { // left
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int i;
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for (i = 0; i < 16; ++i) {
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it->y_left_[i] = ysrc[15 + i * BPS];
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}
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for (i = 0; i < 8; ++i) {
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it->u_left_[i] = uvsrc[7 + i * BPS];
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it->v_left_[i] = uvsrc[15 + i * BPS];
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}
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// top-left (before 'top'!)
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it->y_left_[-1] = it->y_top_[15];
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it->u_left_[-1] = it->uv_top_[0 + 7];
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it->v_left_[-1] = it->uv_top_[8 + 7];
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}
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if (y < enc->mb_h_ - 1) { // top
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memcpy(it->y_top_, ysrc + 15 * BPS, 16);
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memcpy(it->uv_top_, uvsrc + 7 * BPS, 8 + 8);
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}
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}
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int VP8IteratorNext(VP8EncIterator* const it) {
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it->preds_ += 4;
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it->mb_ += 1;
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it->nz_ += 1;
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it->y_top_ += 16;
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it->uv_top_ += 16;
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it->x_ += 1;
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if (it->x_ == it->enc_->mb_w_) {
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VP8IteratorSetRow(it, ++it->y_);
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}
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return (0 < --it->count_down_);
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}
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//------------------------------------------------------------------------------
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// Helper function to set mode properties
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void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode) {
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uint8_t* preds = it->preds_;
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int y;
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for (y = 0; y < 4; ++y) {
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memset(preds, mode, 4);
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preds += it->enc_->preds_w_;
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}
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it->mb_->type_ = 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes) {
|
||
|
|
uint8_t* preds = it->preds_;
|
||
|
|
int y;
|
||
|
|
for (y = 4; y > 0; --y) {
|
||
|
|
memcpy(preds, modes, 4 * sizeof(*modes));
|
||
|
|
preds += it->enc_->preds_w_;
|
||
|
|
modes += 4;
|
||
|
|
}
|
||
|
|
it->mb_->type_ = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode) {
|
||
|
|
it->mb_->uv_mode_ = mode;
|
||
|
|
}
|
||
|
|
|
||
|
|
void VP8SetSkip(const VP8EncIterator* const it, int skip) {
|
||
|
|
it->mb_->skip_ = skip;
|
||
|
|
}
|
||
|
|
|
||
|
|
void VP8SetSegment(const VP8EncIterator* const it, int segment) {
|
||
|
|
it->mb_->segment_ = segment;
|
||
|
|
}
|
||
|
|
|
||
|
|
//------------------------------------------------------------------------------
|
||
|
|
// Intra4x4 sub-blocks iteration
|
||
|
|
//
|
||
|
|
// We store and update the boundary samples into an array of 37 pixels. They
|
||
|
|
// are updated as we iterate and reconstructs each intra4x4 blocks in turn.
|
||
|
|
// The position of the samples has the following snake pattern:
|
||
|
|
//
|
||
|
|
// 16|17 18 19 20|21 22 23 24|25 26 27 28|29 30 31 32|33 34 35 36 <- Top-right
|
||
|
|
// --+-----------+-----------+-----------+-----------+
|
||
|
|
// 15| 19| 23| 27| 31|
|
||
|
|
// 14| 18| 22| 26| 30|
|
||
|
|
// 13| 17| 21| 25| 29|
|
||
|
|
// 12|13 14 15 16|17 18 19 20|21 22 23 24|25 26 27 28|
|
||
|
|
// --+-----------+-----------+-----------+-----------+
|
||
|
|
// 11| 15| 19| 23| 27|
|
||
|
|
// 10| 14| 18| 22| 26|
|
||
|
|
// 9| 13| 17| 21| 25|
|
||
|
|
// 8| 9 10 11 12|13 14 15 16|17 18 19 20|21 22 23 24|
|
||
|
|
// --+-----------+-----------+-----------+-----------+
|
||
|
|
// 7| 11| 15| 19| 23|
|
||
|
|
// 6| 10| 14| 18| 22|
|
||
|
|
// 5| 9| 13| 17| 21|
|
||
|
|
// 4| 5 6 7 8| 9 10 11 12|13 14 15 16|17 18 19 20|
|
||
|
|
// --+-----------+-----------+-----------+-----------+
|
||
|
|
// 3| 7| 11| 15| 19|
|
||
|
|
// 2| 6| 10| 14| 18|
|
||
|
|
// 1| 5| 9| 13| 17|
|
||
|
|
// 0| 1 2 3 4| 5 6 7 8| 9 10 11 12|13 14 15 16|
|
||
|
|
// --+-----------+-----------+-----------+-----------+
|
||
|
|
|
||
|
|
// Array to record the position of the top sample to pass to the prediction
|
||
|
|
// functions in dsp.c.
|
||
|
|
static const uint8_t VP8TopLeftI4[16] = {
|
||
|
|
17, 21, 25, 29,
|
||
|
|
13, 17, 21, 25,
|
||
|
|
9, 13, 17, 21,
|
||
|
|
5, 9, 13, 17
|
||
|
|
};
|
||
|
|
|
||
|
|
void VP8IteratorStartI4(VP8EncIterator* const it) {
|
||
|
|
const VP8Encoder* const enc = it->enc_;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
it->i4_ = 0; // first 4x4 sub-block
|
||
|
|
it->i4_top_ = it->i4_boundary_ + VP8TopLeftI4[0];
|
||
|
|
|
||
|
|
// Import the boundary samples
|
||
|
|
for (i = 0; i < 17; ++i) { // left
|
||
|
|
it->i4_boundary_[i] = it->y_left_[15 - i];
|
||
|
|
}
|
||
|
|
for (i = 0; i < 16; ++i) { // top
|
||
|
|
it->i4_boundary_[17 + i] = it->y_top_[i];
|
||
|
|
}
|
||
|
|
// top-right samples have a special case on the far right of the picture
|
||
|
|
if (it->x_ < enc->mb_w_ - 1) {
|
||
|
|
for (i = 16; i < 16 + 4; ++i) {
|
||
|
|
it->i4_boundary_[17 + i] = it->y_top_[i];
|
||
|
|
}
|
||
|
|
} else { // else, replicate the last valid pixel four times
|
||
|
|
for (i = 16; i < 16 + 4; ++i) {
|
||
|
|
it->i4_boundary_[17 + i] = it->i4_boundary_[17 + 15];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
VP8IteratorNzToBytes(it); // import the non-zero context
|
||
|
|
}
|
||
|
|
|
||
|
|
int VP8IteratorRotateI4(VP8EncIterator* const it,
|
||
|
|
const uint8_t* const yuv_out) {
|
||
|
|
const uint8_t* const blk = yuv_out + VP8Scan[it->i4_];
|
||
|
|
uint8_t* const top = it->i4_top_;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
// Update the cache with 7 fresh samples
|
||
|
|
for (i = 0; i <= 3; ++i) {
|
||
|
|
top[-4 + i] = blk[i + 3 * BPS]; // store future top samples
|
||
|
|
}
|
||
|
|
if ((it->i4_ & 3) != 3) { // if not on the right sub-blocks #3, #7, #11, #15
|
||
|
|
for (i = 0; i <= 2; ++i) { // store future left samples
|
||
|
|
top[i] = blk[3 + (2 - i) * BPS];
|
||
|
|
}
|
||
|
|
} else { // else replicate top-right samples, as says the specs.
|
||
|
|
for (i = 0; i <= 3; ++i) {
|
||
|
|
top[i] = top[i + 4];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// move pointers to next sub-block
|
||
|
|
++it->i4_;
|
||
|
|
if (it->i4_ == 16) { // we're done
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
it->i4_top_ = it->i4_boundary_ + VP8TopLeftI4[it->i4_];
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
//------------------------------------------------------------------------------
|
||
|
|
|