/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "get_bits.h"
#include "golomb.h"
#include "h264.h"
#include "h264_parse.h"
int ff_h264_pred_weight_table(GetBitContext *gb, const SPS *sps,
const int *ref_count, int slice_type_nos,
H264PredWeightTable *pwt)
{
int list, i;
int luma_def, chroma_def;
pwt->use_weight = 0;
pwt->use_weight_chroma = 0;
pwt->luma_log2_weight_denom = get_ue_golomb(gb);
if (sps->chroma_format_idc)
pwt->chroma_log2_weight_denom = get_ue_golomb(gb);
if (pwt->luma_log2_weight_denom > 7U) {
av_log(NULL, AV_LOG_ERROR, "luma_log2_weight_denom %d is out of range\n", pwt->luma_log2_weight_denom);
pwt->luma_log2_weight_denom = 0;
}
if (pwt->chroma_log2_weight_denom > 7U) {
av_log(NULL, AV_LOG_ERROR, "chroma_log2_weight_denom %d is out of range\n", pwt->chroma_log2_weight_denom);
pwt->chroma_log2_weight_denom = 0;
}
luma_def = 1 << pwt->luma_log2_weight_denom;
chroma_def = 1 << pwt->chroma_log2_weight_denom;
for (list = 0; list < 2; list++) {
pwt->luma_weight_flag[list] = 0;
pwt->chroma_weight_flag[list] = 0;
for (i = 0; i < ref_count[list]; i++) {
int luma_weight_flag, chroma_weight_flag;
luma_weight_flag = get_bits1(gb);
if (luma_weight_flag) {
pwt->luma_weight[i][list][0] = get_se_golomb(gb);
pwt->luma_weight[i][list][1] = get_se_golomb(gb);
if (pwt->luma_weight[i][list][0] != luma_def ||
pwt->luma_weight[i][list][1] != 0) {
pwt->use_weight = 1;
pwt->luma_weight_flag[list] = 1;
}
} else {
pwt->luma_weight[i][list][0] = luma_def;
pwt->luma_weight[i][list][1] = 0;
}
if (sps->chroma_format_idc) {
chroma_weight_flag = get_bits1(gb);
if (chroma_weight_flag) {
int j;
for (j = 0; j < 2; j++) {
pwt->chroma_weight[i][list][j][0] = get_se_golomb(gb);
pwt->chroma_weight[i][list][j][1] = get_se_golomb(gb);
if (pwt->chroma_weight[i][list][j][0] != chroma_def ||
pwt->chroma_weight[i][list][j][1] != 0) {
pwt->use_weight_chroma = 1;
pwt->chroma_weight_flag[list] = 1;
}
}
} else {
int j;
for (j = 0; j < 2; j++) {
pwt->chroma_weight[i][list][j][0] = chroma_def;
pwt->chroma_weight[i][list][j][1] = 0;
}
}
}
}
if (slice_type_nos != AV_PICTURE_TYPE_B)
break;
}
pwt->use_weight = pwt->use_weight || pwt->use_weight_chroma;
return 0;
}
/**
* Check if the top & left blocks are available if needed and
* change the dc mode so it only uses the available blocks.
*/
int ff_h264_check_intra4x4_pred_mode(int8_t *pred_mode_cache, void *logctx,
int top_samples_available, int left_samples_available)
{
static const int8_t top[12] = {
-1, 0, LEFT_DC_PRED, -1, -1, -1, -1, -1, 0
};
static const int8_t left[12] = {
0, -1, TOP_DC_PRED, 0, -1, -1, -1, 0, -1, DC_128_PRED
};
int i;
if (!(top_samples_available & 0x8000)) {
for (i = 0; i < 4; i++) {
int status = top[pred_mode_cache[scan8[0] + i]];
if (status < 0) {
av_log(logctx, AV_LOG_ERROR,
"top block unavailable for requested intra mode %d\n",
status);
return AVERROR_INVALIDDATA;
} else if (status) {
pred_mode_cache[scan8[0] + i] = status;
}
}
}
if ((left_samples_available & 0x8888) != 0x8888) {
static const int mask[4] = { 0x8000, 0x2000, 0x80, 0x20 };
for (i = 0; i < 4; i++)
if (!(left_samples_available & mask[i])) {
int status = left[pred_mode_cache[scan8[0] + 8 * i]];
if (status < 0) {
av_log(logctx, AV_LOG_ERROR,
"left block unavailable for requested intra4x4 mode %d\n",
status);
return AVERROR_INVALIDDATA;
} else if (status) {
pred_mode_cache[scan8[0] + 8 * i] = status;
}
}
}
return 0;
}
/**
* Check if the top & left blocks are available if needed and
* change the dc mode so it only uses the available blocks.
*/
int ff_h264_check_intra_pred_mode(void *logctx, int top_samples_available,
int left_samples_available,
int mode, int is_chroma)
{
static const int8_t top[4] = { LEFT_DC_PRED8x8, 1, -1, -1 };
static const int8_t left[5] = { TOP_DC_PRED8x8, -1, 2, -1, DC_128_PRED8x8 };
if (mode > 3U) {
av_log(logctx, AV_LOG_ERROR,
"out of range intra chroma pred mode\n");
return AVERROR_INVALIDDATA;
}
if (!(top_samples_available & 0x8000)) {
mode = top[mode];
if (mode < 0) {
av_log(logctx, AV_LOG_ERROR,
"top block unavailable for requested intra mode\n");
return AVERROR_INVALIDDATA;
}
}
if ((left_samples_available & 0x8080) != 0x8080) {
mode = left[mode];
if (mode < 0) {
av_log(logctx, AV_LOG_ERROR,
"left block unavailable for requested intra mode\n");
return AVERROR_INVALIDDATA;
}
if (is_chroma && (left_samples_available & 0x8080)) {
// mad cow disease mode, aka MBAFF + constrained_intra_pred
mode = ALZHEIMER_DC_L0T_PRED8x8 +
(!(left_samples_available & 0x8000)) +
2 * (mode == DC_128_PRED8x8);
}
}
return mode;
}