Add WebP library to Chromium...

third_party/libwebp/frame.c

+// Copyright 2010 Google Inc.
+//
+// This code is licensed under the same terms as WebM:
+//  Software License Agreement:  http://www.webmproject.org/license/software/
+//  Additional IP Rights Grant:  http://www.webmproject.org/license/additional/
+// -----------------------------------------------------------------------------
+//
+// Frame-reconstruction function. Memory allocation.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <stdlib.h>
+#include "vp8i.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+#define ALIGN_MASK (32 - 1)
+
+//-----------------------------------------------------------------------------
+// Memory setup
+
+// how many extra luma lines are needed for caching, given a filtering level
+static const uint8_t kFilterExtraRows[3] = { 0, 4, 8 };
+
+int VP8InitFrame(VP8Decoder* const dec, VP8Io* io) {
+  const int mb_w = dec->mb_w_;
+  const int intra_pred_mode_size = 4 * mb_w * sizeof(uint8_t);
+  const int top_size = (16 + 8 + 8) * mb_w;
+  const int info_size = (mb_w + 1) * sizeof(VP8MB);
+  const int yuv_size = YUV_SIZE * sizeof(*dec->yuv_b_);
+  const int coeffs_size = 384 * sizeof(*dec->coeffs_);
+  const int cache_height = (dec->filter_type_ == 0) ? 0 :
+                           (16 + kFilterExtraRows[dec->filter_type_]) * 3 / 2;
+  const int cache_size = top_size * cache_height;
+  const int needed = intra_pred_mode_size
+                   + top_size + info_size
+                   + yuv_size + coeffs_size
+                   + cache_size + ALIGN_MASK;
+  if (needed > dec->mem_size_) {
+    free(dec->mem_);
+    dec->mem_size_ = 0;
+    dec->mem_ = (uint8_t*)malloc(needed);
+    if (dec->mem_ == NULL) {
+      return VP8SetError(dec, 1, "no memory during frame initialization.");
+    }
+    dec->mem_size_ = needed;
+  }
+
+  uint8_t* mem = (uint8_t*)dec->mem_;
+  dec->intra_t_ = (uint8_t*)mem;
+  mem += intra_pred_mode_size;
+
+  dec->y_t_ = (uint8_t*)mem;
+  mem += 16 * mb_w;
+  dec->u_t_ = (uint8_t*)mem;
+  mem += 8 * mb_w;
+  dec->v_t_ = (uint8_t*)mem;
+  mem += 8 * mb_w;
+
+  dec->mb_info_ = ((VP8MB*)mem) + 1;
+  mem += info_size;
+
+  mem = (uint8_t*)((uint64_t)(mem + ALIGN_MASK) & ~ALIGN_MASK);
+  assert((yuv_size & ALIGN_MASK) == 0);
+  dec->yuv_b_ = (uint8_t*)mem;
+  mem += yuv_size;
+
+  dec->coeffs_ = (int16_t*)mem;
+  mem += coeffs_size;
+
+  dec->cache_y_stride_ = 16 * mb_w;
+  dec->cache_uv_stride_ = 8 * mb_w;
+  if (dec->filter_type_ == 0) {
+    dec->cache_y_ = NULL;
+    dec->cache_u_ = NULL;
+    dec->cache_v_ = NULL;
+  } else {
+    const int extra_rows = kFilterExtraRows[dec->filter_type_];
+    const int extra_y = extra_rows * dec->cache_y_stride_;
+    const int extra_uv =(extra_rows / 2) * dec->cache_uv_stride_;
+    dec->cache_y_ = ((uint8_t*)mem) + extra_y;
+    dec->cache_u_ = dec->cache_y_ + 16 * dec->cache_y_stride_ + extra_uv;
+    dec->cache_v_ = dec->cache_u_ + 8 * dec->cache_uv_stride_ + extra_uv;
+  }
+  mem += cache_size;
+
+  // note: left-info is initialized once for all.
+  memset(dec->mb_info_ - 1, 0, (mb_w + 1) * sizeof(*dec->mb_info_));
+
+  // initialize top
+  memset(dec->intra_t_, B_DC_PRED, intra_pred_mode_size);
+
+  // prepare 'io'
+  io->width = dec->pic_hdr_.width_;
+  io->height = dec->pic_hdr_.height_;
+  io->mb_x = 0;
+  io->mb_y = 0;
+  if (dec->filter_type_ == 0) {
+    io->y = dec->yuv_b_ + Y_OFF;
+    io->u = dec->yuv_b_ + U_OFF;
+    io->v = dec->yuv_b_ + V_OFF;
+    io->y_stride = BPS;
+    io->uv_stride = BPS;
+  } else {
+    io->y = dec->cache_y_;
+    io->u = dec->cache_u_;
+    io->v = dec->cache_v_;
+    io->y_stride = dec->cache_y_stride_;
+    io->uv_stride = dec->cache_uv_stride_;
+    io->mb_w = io->width;
+  }
+
+  // Init critical function pointers and look-up tables.
+  VP8DspInitTables();
+  VP8DspInit();
+
+  return 1;
+}
+
+//-----------------------------------------------------------------------------
+// Filtering
+
+static inline int hev_thresh_from_level(int level, int keyframe) {
+  if (keyframe) {
+    return (level >= 40) ? 2 : (level >= 15) ? 1 : 0;
+  } else {
+    return (level >= 40) ? 3 : (level >= 20) ? 2 : (level >= 15) ? 1 : 0;
+  }
+}
+
+static void DoFilter(VP8Decoder* const dec, int mb_x, int mb_y) {
+  VP8MB* const mb = dec->mb_info_ + mb_x;
+  uint8_t* const y_dst = dec->cache_y_ + mb_x * 16;
+  const int y_bps = dec->cache_y_stride_;
+  const int level = mb->f_level_;
+  const int ilevel = mb->f_ilevel_;
+  const int limit = 2 * level + ilevel;
+  if (dec->filter_type_ == 1) {   // simple
+    if (mb_x > 0) {
+      VP8SimpleHFilter16(y_dst, y_bps, limit + 4);
+    }
+    if (mb->f_inner_) {
+      VP8SimpleHFilter16i(y_dst, y_bps, limit);
+    }
+    if (mb_y > 0) {
+      VP8SimpleVFilter16(y_dst, y_bps, limit + 4);
+    }
+    if (mb->f_inner_) {
+      VP8SimpleVFilter16i(y_dst, y_bps, limit);
+    }
+  } else {    // complex
+    uint8_t* const u_dst = dec->cache_u_ + mb_x * 8;
+    uint8_t* const v_dst = dec->cache_v_ + mb_x * 8;
+    const int uv_bps = dec->cache_uv_stride_;
+    const int hev_thresh =
+        hev_thresh_from_level(level, dec->frm_hdr_.key_frame_);
+    if (mb_x > 0) {
+      VP8HFilter16(y_dst, y_bps, limit + 4, ilevel, hev_thresh);
+      VP8HFilter8(u_dst, v_dst, uv_bps, limit + 4, ilevel, hev_thresh);
+    }
+    if (mb->f_inner_) {
+      VP8HFilter16i(y_dst, y_bps, limit, ilevel, hev_thresh);
+      VP8HFilter8i(u_dst, v_dst, uv_bps, limit, ilevel, hev_thresh);
+    }
+    if (mb_y > 0) {
+      VP8VFilter16(y_dst, y_bps, limit + 4, ilevel, hev_thresh);
+      VP8VFilter8(u_dst, v_dst, uv_bps, limit + 4, ilevel, hev_thresh);
+    }
+    if (mb->f_inner_) {
+      VP8VFilter16i(y_dst, y_bps, limit, ilevel, hev_thresh);
+      VP8VFilter8i(u_dst, v_dst, uv_bps, limit, ilevel, hev_thresh);
+    }
+  }
+}
+
+void VP8StoreBlock(VP8Decoder* const dec) {
+  VP8MB* const info = dec->mb_info_ + dec->mb_x_;
+  int level = dec->filter_levels_[dec->segment_];
+  if (dec->filter_hdr_.use_lf_delta_) {
+    // TODO(skal): only CURRENT is handled for now.
+    level += dec->filter_hdr_.ref_lf_delta_[0];
+    if (dec->is_i4x4_) {
+      level += dec->filter_hdr_.mode_lf_delta_[0];
+    }
+  }
+  level = (level < 0) ? 0 : (level > 63) ? 63 : level;
+  info->f_level_ = level;
+
+  if (dec->filter_hdr_.sharpness_ > 0) {
+    if (dec->filter_hdr_.sharpness_ > 4) {
+      level >>= 2;
+    } else {
+      level >>= 1;
+    }
+    if (level > 9 - dec->filter_hdr_.sharpness_) {
+      level = 9 - dec->filter_hdr_.sharpness_;
+    }
+  }
+  info->f_ilevel_ = (level < 1) ? 1 : level;
+  info->f_inner_ = (!info->skip_ || dec->is_i4x4_);
+
+  // Transfer samples to row cache
+  uint8_t* const ydst = dec->cache_y_ + dec->mb_x_ * 16;
+  uint8_t* const udst = dec->cache_u_ + dec->mb_x_ * 8;
+  uint8_t* const vdst = dec->cache_v_ + dec->mb_x_ * 8;
+  for (int y = 0; y < 16; ++y) {
+    memcpy(ydst + y * dec->cache_y_stride_,
+           dec->yuv_b_ + Y_OFF + y * BPS, 16);
+  }
+  for (int y = 0; y < 8; ++y) {
+    memcpy(udst + y * dec->cache_uv_stride_,
+           dec->yuv_b_ + U_OFF + y * BPS, 8);
+    memcpy(vdst + y * dec->cache_uv_stride_,
+           dec->yuv_b_ + V_OFF + y * BPS, 8);
+  }
+}
+
+void VP8FilterRow(VP8Decoder* const dec, VP8Io* io) {
+  for (int mb_x = 0; mb_x < dec->mb_w_; ++mb_x) {
+    DoFilter(dec, mb_x, dec->mb_y_);
+  }
+  const int extra_y_rows = kFilterExtraRows[dec->filter_type_];
+  const int ysize = extra_y_rows * dec->cache_y_stride_;
+  const int uvsize = (extra_y_rows / 2) * dec->cache_uv_stride_;
+  uint8_t* const ydst = dec->cache_y_ - ysize;
+  uint8_t* const udst = dec->cache_u_ - uvsize;
+  uint8_t* const vdst = dec->cache_v_ - uvsize;
+  if (io->put) {
+    int y_end;
+    if (dec->mb_y_ > 0) {
+      io->mb_y = dec->mb_y_ * 16 - extra_y_rows;
+      io->y = ydst;
+      io->u = udst;
+      io->v = vdst;
+      if (dec->mb_y_ < dec->mb_h_ - 1) {
+        y_end = io->mb_y + 16;
+      } else {
+        y_end = io->height;   // last macroblock row.
+      }
+    } else {   // first macroblock row.
+      io->mb_y = 0;
+      y_end = 16 - extra_y_rows;
+      io->y = dec->cache_y_;
+      io->u = dec->cache_u_;
+      io->v = dec->cache_v_;
+    }
+    if (y_end > io->height) {
+      y_end = io->height;
+    }
+    io->mb_h = y_end - io->mb_y;
+    io->put(io);
+  }
+  // rotate top samples
+  if (dec->mb_y_ < dec->mb_h_ - 1) {
+    memcpy(ydst, ydst + 16 * dec->cache_y_stride_, ysize);
+    memcpy(udst, udst + 8 * dec->cache_uv_stride_, uvsize);
+    memcpy(vdst, vdst + 8 * dec->cache_uv_stride_, uvsize);
+  }
+}
+
+
+//-----------------------------------------------------------------------------
+// Main reconstruction function.
+
+static const int kScan[16] = {
+  0 +  0 * BPS,  4 +  0 * BPS, 8 +  0 * BPS, 12 +  0 * BPS,
+  0 +  4 * BPS,  4 +  4 * BPS, 8 +  4 * BPS, 12 +  4 * BPS,
+  0 +  8 * BPS,  4 +  8 * BPS, 8 +  8 * BPS, 12 +  8 * BPS,
+  0 + 12 * BPS,  4 + 12 * BPS, 8 + 12 * BPS, 12 + 12 * BPS
+};
+
+static inline int CheckMode(VP8Decoder* const dec, int mode) {
+  if (mode == B_DC_PRED) {
+    if (dec->mb_x_ == 0) {
+      return (dec->mb_y_ == 0) ? B_DC_PRED_NOTOPLEFT : B_DC_PRED_NOLEFT;
+    } else {
+      return (dec->mb_y_ == 0) ? B_DC_PRED_NOTOP : B_DC_PRED;
+    }
+  }
+  return mode;
+}
+
+static inline void Copy32b(uint8_t* dst, uint8_t* src) {
+  *(uint32_t*)dst = *(uint32_t*)src;
+}
+
+void VP8ReconstructBlock(VP8Decoder* const dec) {
+  uint8_t* const y_dst = dec->yuv_b_ + Y_OFF;
+  uint8_t* const u_dst = dec->yuv_b_ + U_OFF;
+  uint8_t* const v_dst = dec->yuv_b_ + V_OFF;
+
+  // Rotate in the left samples from previously decoded block. We move four
+  // pixels at a time for alignment reason, and because of in-loop filter.
+  if (dec->mb_x_ > 0) {
+    for (int j = -1; j < 16; ++j) {
+      Copy32b(&y_dst[j * BPS - 4], &y_dst[j * BPS + 12]);
+    }
+    for (int j = -1; j < 8; ++j) {
+      Copy32b(&u_dst[j * BPS - 4], &u_dst[j * BPS + 4]);
+      Copy32b(&v_dst[j * BPS - 4], &v_dst[j * BPS + 4]);
+    }
+  } else {
+    for (int j = 0; j < 16; ++j) {
+      y_dst[j * BPS - 1] = 129;
+    }
+    for (int j = 0; j < 8; ++j) {
+      u_dst[j * BPS - 1] = 129;
+      v_dst[j * BPS - 1] = 129;
+    }
+    // Init top-left sample on left column too
+    if (dec->mb_y_ > 0) {
+      y_dst[-1 - BPS] = u_dst[-1 - BPS] = v_dst[-1 - BPS] = 129;
+    }
+  }
+
+  // bring top samples into the cache
+  uint8_t* const top_y = dec->y_t_ + dec->mb_x_ * 16;
+  uint8_t* const top_u = dec->u_t_ + dec->mb_x_ * 8;
+  uint8_t* const top_v = dec->v_t_ + dec->mb_x_ * 8;
+  if (dec->mb_y_ > 0) {
+    memcpy(y_dst - BPS, top_y, 16);
+    memcpy(u_dst - BPS, top_u, 8);
+    memcpy(v_dst - BPS, top_v, 8);
+  } else if (dec->mb_x_ == 0) {
+    // we only need to do this init once at block (0,0).
+    // Afterward, it remains valid for the whole topmost row.
+    memset(y_dst - BPS - 1, 127, 16 + 4 + 1);
+    memset(u_dst - BPS - 1, 127, 8 + 1);
+    memset(v_dst - BPS - 1, 127, 8 + 1);
+  }
+
+  // predict and add residuals
+  const int16_t* coeffs = dec->coeffs_;
+  if (dec->is_i4x4_) {   // 4x4
+    uint32_t* const top_right = (uint32_t*)(y_dst - BPS + 16);
+    if (dec->mb_y_ > 0) {
+      if (dec->mb_x_ >= dec->mb_w_ - 1) {    // on rightmost border
+        top_right[0] = top_y[15] * 0x01010101u;
+      } else {
+        memcpy(top_right, top_y + 16, sizeof(*top_right));
+      }
+    }
+    // replicate the top-right pixels below
+    top_right[BPS] = top_right[2 * BPS] = top_right[3 * BPS] = top_right[0];
+
+    // predict and add residues for all 4x4 blocks in turn.
+    for (int n = 0; n < 16; n++) {
+      uint8_t* const dst = y_dst + kScan[n];
+      VP8PredLuma4[dec->imodes_[n]](dst);
+      if (dec->non_zero_ & (1 << n)) {
+        VP8Transform(coeffs + n * 16, dst);
+      } else if (dec->non_zero_ & (1 << n)) {  // only DC is present
+        VP8TransformDC(coeffs + n * 16, dst);
+      }
+    }
+  } else {    // 16x16
+    const int pred_func = CheckMode(dec, dec->imodes_[0]);
+    VP8PredLuma16[pred_func](y_dst);
+    if (dec->non_zero_) {
+      for (int n = 0; n < 16; n++) {
+        uint8_t* const dst = y_dst + kScan[n];
+        if (dec->non_zero_ac_ & (1 << n)) {
+          VP8Transform(coeffs + n * 16, dst);
+        } else if (dec->non_zero_ & (1 << n)) {  // only DC is present
+          VP8TransformDC(coeffs + n * 16, dst);
+        }
+      }
+    }
+  }
+
+  // Chroma
+  const int pred_func = CheckMode(dec, dec->uvmode_);
+  VP8PredChroma8[pred_func](u_dst);
+  VP8PredChroma8[pred_func](v_dst);
+
+  if (dec->non_zero_ & 0x0f0000) {   // chroma-U
+    const int16_t* const u_coeffs = dec->coeffs_ + 16 * 16;
+    if (dec->non_zero_ac_ & 0x0f0000) {
+      VP8TransformUV(u_coeffs, u_dst);
+    } else {
+      VP8TransformDCUV(u_coeffs, u_dst);
+    }
+  }
+  if (dec->non_zero_ & 0xf00000) {   // chroma-V
+    const int16_t* const v_coeffs = dec->coeffs_ + 20 * 16;
+    if (dec->non_zero_ac_ & 0xf00000) {
+      VP8TransformUV(v_coeffs, v_dst);
+    } else {
+      VP8TransformDCUV(v_coeffs, v_dst);
+    }
+  }
+
+  // stash away top samples for next block
+  if (dec->mb_y_ < dec->mb_h_ - 1) {
+    memcpy(top_y, y_dst + 15 * BPS, 16);
+    memcpy(top_u, u_dst +  7 * BPS,  8);
+    memcpy(top_v, v_dst +  7 * BPS,  8);
+  }
+}
+
+//-----------------------------------------------------------------------------
+
+#if defined(__cplusplus) || defined(c_plusplus)
+}    // extern "C"
+#endif