The Tor Browser: media/libvpx/vp9/common/vp9_blockd.h@ac0c01689b40 (annotated)

media/libvpx/vp9/common/vp9_blockd.h@ac0c01689b40 (annotated)

media/libvpx/vp9/common/vp9_blockd.h

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #ifndef VP9_COMMON_VP9_BLOCKD_H_
 #define VP9_COMMON_VP9_BLOCKD_H_
 #include "./vpx_config.h"
 #include "vpx_ports/mem.h"
 #include "vpx_scale/yv12config.h"
 #include "vp9/common/vp9_common.h"
 #include "vp9/common/vp9_common_data.h"
 #include "vp9/common/vp9_enums.h"
 #include "vp9/common/vp9_filter.h"
 #include "vp9/common/vp9_mv.h"
 #include "vp9/common/vp9_scale.h"
 #include "vp9/common/vp9_seg_common.h"
 #include "vp9/common/vp9_treecoder.h"
 #define BLOCK_SIZE_GROUPS   4
 #define MBSKIP_CONTEXTS 3
 /* Segment Feature Masks */
 #define MAX_MV_REF_CANDIDATES 2
 #define INTRA_INTER_CONTEXTS 4
 #define COMP_INTER_CONTEXTS 5
 #define REF_CONTEXTS 5
 typedef enum {
   PLANE_TYPE_Y_WITH_DC,
   PLANE_TYPE_UV,
 } PLANE_TYPE;
 typedef char ENTROPY_CONTEXT;
 typedef char PARTITION_CONTEXT;
 static INLINE int combine_entropy_contexts(ENTROPY_CONTEXT a,
                                            ENTROPY_CONTEXT b) {
   return (a != 0) + (b != 0);
 }
 typedef enum {
   KEY_FRAME = 0,
   INTER_FRAME = 1,
   FRAME_TYPES,
 } FRAME_TYPE;
 typedef enum {
   DC_PRED,         // Average of above and left pixels
   V_PRED,          // Vertical
   H_PRED,          // Horizontal
   D45_PRED,        // Directional 45  deg = round(arctan(1/1) * 180/pi)
   D135_PRED,       // Directional 135 deg = 180 - 45
   D117_PRED,       // Directional 117 deg = 180 - 63
   D153_PRED,       // Directional 153 deg = 180 - 27
   D207_PRED,       // Directional 207 deg = 180 + 27
   D63_PRED,        // Directional 63  deg = round(arctan(2/1) * 180/pi)
   TM_PRED,         // True-motion
   NEARESTMV,
   NEARMV,
   ZEROMV,
   NEWMV,
   MB_MODE_COUNT
 } MB_PREDICTION_MODE;
 static INLINE int is_inter_mode(MB_PREDICTION_MODE mode) {
   return mode >= NEARESTMV && mode <= NEWMV;
 }
 #define INTRA_MODES (TM_PRED + 1)
 #define INTER_MODES (1 + NEWMV - NEARESTMV)
 #define INTER_OFFSET(mode) ((mode) - NEARESTMV)
 /* For keyframes, intra block modes are predicted by the (already decoded)
    modes for the Y blocks to the left and above us; for interframes, there
    is a single probability table. */
 typedef struct {
   MB_PREDICTION_MODE as_mode;
   int_mv as_mv[2];  // first, second inter predictor motion vectors
 } b_mode_info;
 typedef enum {
   NONE = -1,
   INTRA_FRAME = 0,
   LAST_FRAME = 1,
   GOLDEN_FRAME = 2,
   ALTREF_FRAME = 3,
   MAX_REF_FRAMES = 4
 } MV_REFERENCE_FRAME;
 static INLINE int b_width_log2(BLOCK_SIZE sb_type) {
   return b_width_log2_lookup[sb_type];
 }
 static INLINE int b_height_log2(BLOCK_SIZE sb_type) {
   return b_height_log2_lookup[sb_type];
 }
 static INLINE int mi_width_log2(BLOCK_SIZE sb_type) {
   return mi_width_log2_lookup[sb_type];
 }
 static INLINE int mi_height_log2(BLOCK_SIZE sb_type) {
   return mi_height_log2_lookup[sb_type];
 }
 // This structure now relates to 8x8 block regions.
 typedef struct {
   MB_PREDICTION_MODE mode, uv_mode;
   MV_REFERENCE_FRAME ref_frame[2];
   TX_SIZE tx_size;
   int_mv mv[2];                // for each reference frame used
   int_mv ref_mvs[MAX_REF_FRAMES][MAX_MV_REF_CANDIDATES];
   int_mv best_mv[2];
   uint8_t mode_context[MAX_REF_FRAMES];
   unsigned char skip_coeff;    // 0=need to decode coeffs, 1=no coefficients
   unsigned char segment_id;    // Segment id for this block.
   // Flags used for prediction status of various bit-stream signals
   unsigned char seg_id_predicted;
   INTERPOLATION_TYPE interp_filter;
   BLOCK_SIZE sb_type;
 } MB_MODE_INFO;
 typedef struct {
   MB_MODE_INFO mbmi;
   b_mode_info bmi[4];
 } MODE_INFO;
 static INLINE int is_inter_block(const MB_MODE_INFO *mbmi) {
   return mbmi->ref_frame[0] > INTRA_FRAME;
 }
 static INLINE int has_second_ref(const MB_MODE_INFO *mbmi) {
   return mbmi->ref_frame[1] > INTRA_FRAME;
 }
 enum mv_precision {
   MV_PRECISION_Q3,
   MV_PRECISION_Q4
 };
 #if CONFIG_ALPHA
 enum { MAX_MB_PLANE = 4 };
 #else
 enum { MAX_MB_PLANE = 3 };
 #endif
 struct buf_2d {
   uint8_t *buf;
   int stride;
 };
 struct macroblockd_plane {
   int16_t *qcoeff;
   int16_t *dqcoeff;
   uint16_t *eobs;
   PLANE_TYPE plane_type;
   int subsampling_x;
   int subsampling_y;
   struct buf_2d dst;
   struct buf_2d pre[2];
   int16_t *dequant;
   ENTROPY_CONTEXT *above_context;
   ENTROPY_CONTEXT *left_context;
 };
 #define BLOCK_OFFSET(x, i) ((x) + (i) * 16)
 typedef struct macroblockd {
   struct macroblockd_plane plane[MAX_MB_PLANE];
   struct scale_factors scale_factor[2];
   MODE_INFO *last_mi;
   int mode_info_stride;
   // A NULL indicates that the 8x8 is not part of the image
   MODE_INFO **mi_8x8;
   MODE_INFO **prev_mi_8x8;
   MODE_INFO *mi_stream;
   int up_available;
   int left_available;
   /* Distance of MB away from frame edges */
   int mb_to_left_edge;
   int mb_to_right_edge;
   int mb_to_top_edge;
   int mb_to_bottom_edge;
   int lossless;
   /* Inverse transform function pointers. */
   void (*itxm_add)(const int16_t *input, uint8_t *dest, int stride, int eob);
   struct subpix_fn_table  subpix;
   int corrupted;
   /* Y,U,V,(A) */
   ENTROPY_CONTEXT *above_context[MAX_MB_PLANE];
   ENTROPY_CONTEXT left_context[MAX_MB_PLANE][16];
   PARTITION_CONTEXT *above_seg_context;
   PARTITION_CONTEXT left_seg_context[8];
 } MACROBLOCKD;
 static BLOCK_SIZE get_subsize(BLOCK_SIZE bsize, PARTITION_TYPE partition) {
   const BLOCK_SIZE subsize = subsize_lookup[partition][bsize];
   assert(subsize < BLOCK_SIZES);
   return subsize;
 }
 extern const TX_TYPE mode2txfm_map[MB_MODE_COUNT];
 static INLINE TX_TYPE get_tx_type_4x4(PLANE_TYPE plane_type,
                                       const MACROBLOCKD *xd, int ib) {
   const MODE_INFO *const mi = xd->mi_8x8[0];
   const MB_MODE_INFO *const mbmi = &mi->mbmi;
   if (plane_type != PLANE_TYPE_Y_WITH_DC ||
       xd->lossless ||
       is_inter_block(mbmi))
     return DCT_DCT;
   return mode2txfm_map[mbmi->sb_type < BLOCK_8X8 ?
                        mi->bmi[ib].as_mode : mbmi->mode];
 }
 static INLINE TX_TYPE get_tx_type_8x8(PLANE_TYPE plane_type,
                                       const MACROBLOCKD *xd) {
   return plane_type == PLANE_TYPE_Y_WITH_DC ?
              mode2txfm_map[xd->mi_8x8[0]->mbmi.mode] : DCT_DCT;
 }
 static INLINE TX_TYPE get_tx_type_16x16(PLANE_TYPE plane_type,
                                         const MACROBLOCKD *xd) {
   return plane_type == PLANE_TYPE_Y_WITH_DC ?
              mode2txfm_map[xd->mi_8x8[0]->mbmi.mode] : DCT_DCT;
 }
 static void setup_block_dptrs(MACROBLOCKD *xd, int ss_x, int ss_y) {
   int i;
   for (i = 0; i < MAX_MB_PLANE; i++) {
     xd->plane[i].plane_type = i ? PLANE_TYPE_UV : PLANE_TYPE_Y_WITH_DC;
     xd->plane[i].subsampling_x = i ? ss_x : 0;
     xd->plane[i].subsampling_y = i ? ss_y : 0;
   }
 #if CONFIG_ALPHA
   // TODO(jkoleszar): Using the Y w/h for now
   xd->plane[3].subsampling_x = 0;
   xd->plane[3].subsampling_y = 0;
 #endif
 }
 static INLINE TX_SIZE get_uv_tx_size(const MB_MODE_INFO *mbmi) {
   return MIN(mbmi->tx_size, max_uv_txsize_lookup[mbmi->sb_type]);
 }
 static BLOCK_SIZE get_plane_block_size(BLOCK_SIZE bsize,
                                        const struct macroblockd_plane *pd) {
   BLOCK_SIZE bs = ss_size_lookup[bsize][pd->subsampling_x][pd->subsampling_y];
   assert(bs < BLOCK_SIZES);
   return bs;
 }
 static INLINE int plane_block_width(BLOCK_SIZE bsize,
                                     const struct macroblockd_plane* plane) {
   return 4 << (b_width_log2(bsize) - plane->subsampling_x);
 }
 static INLINE int plane_block_height(BLOCK_SIZE bsize,
                                      const struct macroblockd_plane* plane) {
   return 4 << (b_height_log2(bsize) - plane->subsampling_y);
 }
 typedef void (*foreach_transformed_block_visitor)(int plane, int block,
                                                   BLOCK_SIZE plane_bsize,
                                                   TX_SIZE tx_size,
                                                   void *arg);
 static INLINE void foreach_transformed_block_in_plane(
     const MACROBLOCKD *const xd, BLOCK_SIZE bsize, int plane,
     foreach_transformed_block_visitor visit, void *arg) {
   const struct macroblockd_plane *const pd = &xd->plane[plane];
   const MB_MODE_INFO* mbmi = &xd->mi_8x8[0]->mbmi;
   // block and transform sizes, in number of 4x4 blocks log 2 ("*_b")
   // 4x4=0, 8x8=2, 16x16=4, 32x32=6, 64x64=8
   // transform size varies per plane, look it up in a common way.
   const TX_SIZE tx_size = plane ? get_uv_tx_size(mbmi)
                                 : mbmi->tx_size;
   const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
   const int num_4x4_w = num_4x4_blocks_wide_lookup[plane_bsize];
   const int num_4x4_h = num_4x4_blocks_high_lookup[plane_bsize];
   const int step = 1 << (tx_size << 1);
   int i;
   // If mb_to_right_edge is < 0 we are in a situation in which
   // the current block size extends into the UMV and we won't
   // visit the sub blocks that are wholly within the UMV.
   if (xd->mb_to_right_edge < 0 || xd->mb_to_bottom_edge < 0) {
     int r, c;
     int max_blocks_wide = num_4x4_w;
     int max_blocks_high = num_4x4_h;
     // xd->mb_to_right_edge is in units of pixels * 8.  This converts
     // it to 4x4 block sizes.
     if (xd->mb_to_right_edge < 0)
       max_blocks_wide += (xd->mb_to_right_edge >> (5 + pd->subsampling_x));
     if (xd->mb_to_bottom_edge < 0)
       max_blocks_high += (xd->mb_to_bottom_edge >> (5 + pd->subsampling_y));
     i = 0;
     // Unlike the normal case - in here we have to keep track of the
     // row and column of the blocks we use so that we know if we are in
     // the unrestricted motion border.
     for (r = 0; r < num_4x4_h; r += (1 << tx_size)) {
       for (c = 0; c < num_4x4_w; c += (1 << tx_size)) {
         if (r < max_blocks_high && c < max_blocks_wide)
           visit(plane, i, plane_bsize, tx_size, arg);
         i += step;
       }
     }
   } else {
     for (i = 0; i < num_4x4_w * num_4x4_h; i += step)
       visit(plane, i, plane_bsize, tx_size, arg);
   }
 }
 static INLINE void foreach_transformed_block(
     const MACROBLOCKD* const xd, BLOCK_SIZE bsize,
     foreach_transformed_block_visitor visit, void *arg) {
   int plane;
   for (plane = 0; plane < MAX_MB_PLANE; plane++)
     foreach_transformed_block_in_plane(xd, bsize, plane, visit, arg);
 }
 static INLINE void foreach_transformed_block_uv(
     const MACROBLOCKD* const xd, BLOCK_SIZE bsize,
     foreach_transformed_block_visitor visit, void *arg) {
   int plane;
   for (plane = 1; plane < MAX_MB_PLANE; plane++)
     foreach_transformed_block_in_plane(xd, bsize, plane, visit, arg);
 }
 static int raster_block_offset(BLOCK_SIZE plane_bsize,
                                int raster_block, int stride) {
   const int bw = b_width_log2(plane_bsize);
   const int y = 4 * (raster_block >> bw);
   const int x = 4 * (raster_block & ((1 << bw) - 1));
   return y * stride + x;
 }
 static int16_t* raster_block_offset_int16(BLOCK_SIZE plane_bsize,
                                           int raster_block, int16_t *base) {
   const int stride = 4 << b_width_log2(plane_bsize);
   return base + raster_block_offset(plane_bsize, raster_block, stride);
 }
 static uint8_t* raster_block_offset_uint8(BLOCK_SIZE plane_bsize,
                                           int raster_block, uint8_t *base,
                                           int stride) {
   return base + raster_block_offset(plane_bsize, raster_block, stride);
 }
 static int txfrm_block_to_raster_block(BLOCK_SIZE plane_bsize,
                                        TX_SIZE tx_size, int block) {
   const int bwl = b_width_log2(plane_bsize);
   const int tx_cols_log2 = bwl - tx_size;
   const int tx_cols = 1 << tx_cols_log2;
   const int raster_mb = block >> (tx_size << 1);
   const int x = (raster_mb & (tx_cols - 1)) << tx_size;
   const int y = (raster_mb >> tx_cols_log2) << tx_size;
   return x + (y << bwl);
 }
 static void txfrm_block_to_raster_xy(BLOCK_SIZE plane_bsize,
                                      TX_SIZE tx_size, int block,
                                      int *x, int *y) {
   const int bwl = b_width_log2(plane_bsize);
   const int tx_cols_log2 = bwl - tx_size;
   const int tx_cols = 1 << tx_cols_log2;
   const int raster_mb = block >> (tx_size << 1);
   *x = (raster_mb & (tx_cols - 1)) << tx_size;
   *y = (raster_mb >> tx_cols_log2) << tx_size;
 }
 static void extend_for_intra(MACROBLOCKD *xd, BLOCK_SIZE plane_bsize,
                              int plane, int block, TX_SIZE tx_size) {
   struct macroblockd_plane *const pd = &xd->plane[plane];
   uint8_t *const buf = pd->dst.buf;
   const int stride = pd->dst.stride;
   int x, y;
   txfrm_block_to_raster_xy(plane_bsize, tx_size, block, &x, &y);
   x = x * 4 - 1;
   y = y * 4 - 1;
   // Copy a pixel into the umv if we are in a situation where the block size
   // extends into the UMV.
   // TODO(JBB): Should be able to do the full extend in place so we don't have
   // to do this multiple times.
   if (xd->mb_to_right_edge < 0) {
     const int bw = 4 << b_width_log2(plane_bsize);
     const int umv_border_start = bw + (xd->mb_to_right_edge >>
                                        (3 + pd->subsampling_x));
     if (x + bw > umv_border_start)
       vpx_memset(&buf[y * stride + umv_border_start],
                  buf[y * stride + umv_border_start - 1], bw);
   }
   if (xd->mb_to_bottom_edge < 0) {
     if (xd->left_available || x >= 0) {
       const int bh = 4 << b_height_log2(plane_bsize);
       const int umv_border_start =
           bh + (xd->mb_to_bottom_edge >> (3 + pd->subsampling_y));
       if (y + bh > umv_border_start) {
         const uint8_t c = buf[(umv_border_start - 1) * stride + x];
         uint8_t *d = &buf[umv_border_start * stride + x];
         int i;
         for (i = 0; i < bh; ++i, d += stride)
           *d = c;
       }
     }
   }
 }
 static void set_contexts(const MACROBLOCKD *xd, struct macroblockd_plane *pd,
                          BLOCK_SIZE plane_bsize, TX_SIZE tx_size,
                          int has_eob, int aoff, int loff) {
   ENTROPY_CONTEXT *const a = pd->above_context + aoff;
   ENTROPY_CONTEXT *const l = pd->left_context + loff;
   const int tx_size_in_blocks = 1 << tx_size;
   // above
   if (has_eob && xd->mb_to_right_edge < 0) {
     int i;
     const int blocks_wide = num_4x4_blocks_wide_lookup[plane_bsize] +
                             (xd->mb_to_right_edge >> (5 + pd->subsampling_x));
     int above_contexts = tx_size_in_blocks;
     if (above_contexts + aoff > blocks_wide)
       above_contexts = blocks_wide - aoff;
     for (i = 0; i < above_contexts; ++i)
       a[i] = has_eob;
     for (i = above_contexts; i < tx_size_in_blocks; ++i)
       a[i] = 0;
   } else {
     vpx_memset(a, has_eob, sizeof(ENTROPY_CONTEXT) * tx_size_in_blocks);
   }
   // left
   if (has_eob && xd->mb_to_bottom_edge < 0) {
     int i;
     const int blocks_high = num_4x4_blocks_high_lookup[plane_bsize] +
                             (xd->mb_to_bottom_edge >> (5 + pd->subsampling_y));
     int left_contexts = tx_size_in_blocks;
     if (left_contexts + loff > blocks_high)
       left_contexts = blocks_high - loff;
     for (i = 0; i < left_contexts; ++i)
       l[i] = has_eob;
     for (i = left_contexts; i < tx_size_in_blocks; ++i)
       l[i] = 0;
   } else {
     vpx_memset(l, has_eob, sizeof(ENTROPY_CONTEXT) * tx_size_in_blocks);
   }
 }
 static int get_tx_eob(const struct segmentation *seg, int segment_id,
                       TX_SIZE tx_size) {
   const int eob_max = 16 << (tx_size << 1);
   return vp9_segfeature_active(seg, segment_id, SEG_LVL_SKIP) ? 0 : eob_max;
 }
 #endif  // VP9_COMMON_VP9_BLOCKD_H_

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media/libvpx/vp9/common/vp9_blockd.h@ac0c01689b40 (annotated)

media/libvpx/vp9/common/vp9_blockd.h