/* * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; 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); 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 intra4x4 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 (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); } if (mode < 0) { av_log(logctx, AV_LOG_ERROR, "left block unavailable for requested intra mode\n"); return AVERROR_INVALIDDATA; } } return mode; } int ff_h264_parse_ref_count(int *plist_count, int ref_count[2], GetBitContext *gb, const PPS *pps, int slice_type_nos, int picture_structure) { int list_count; int num_ref_idx_active_override_flag, max_refs; // set defaults, might be overridden a few lines later ref_count[0] = pps->ref_count[0]; ref_count[1] = pps->ref_count[1]; if (slice_type_nos != AV_PICTURE_TYPE_I) { num_ref_idx_active_override_flag = get_bits1(gb); if (num_ref_idx_active_override_flag) { ref_count[0] = get_ue_golomb(gb) + 1; if (ref_count[0] < 1) goto fail; if (slice_type_nos == AV_PICTURE_TYPE_B) { ref_count[1] = get_ue_golomb(gb) + 1; if (ref_count[1] < 1) goto fail; } } if (slice_type_nos == AV_PICTURE_TYPE_B) list_count = 2; else list_count = 1; } else { list_count = 0; ref_count[0] = ref_count[1] = 0; } max_refs = picture_structure == PICT_FRAME ? 16 : 32; if (ref_count[0] > max_refs || ref_count[1] > max_refs) goto fail; *plist_count = list_count; return 0; fail: *plist_count = 0; ref_count[0] = 0; ref_count[1] = 0; return AVERROR_INVALIDDATA; } int ff_h264_init_poc(int pic_field_poc[2], int *pic_poc, const SPS *sps, H264POCContext *pc, int picture_structure, int nal_ref_idc) { const int max_frame_num = 1 << sps->log2_max_frame_num; int field_poc[2]; pc->frame_num_offset = pc->prev_frame_num_offset; if (pc->frame_num < pc->prev_frame_num) pc->frame_num_offset += max_frame_num; if (sps->poc_type == 0) { const int max_poc_lsb = 1 << sps->log2_max_poc_lsb; if (pc->poc_lsb < pc->prev_poc_lsb && pc->prev_poc_lsb - pc->poc_lsb >= max_poc_lsb / 2) pc->poc_msb = pc->prev_poc_msb + max_poc_lsb; else if (pc->poc_lsb > pc->prev_poc_lsb && pc->prev_poc_lsb - pc->poc_lsb < -max_poc_lsb / 2) pc->poc_msb = pc->prev_poc_msb - max_poc_lsb; else pc->poc_msb = pc->prev_poc_msb; field_poc[0] = field_poc[1] = pc->poc_msb + pc->poc_lsb; if (picture_structure == PICT_FRAME) field_poc[1] += pc->delta_poc_bottom; } else if (sps->poc_type == 1) { int abs_frame_num, expected_delta_per_poc_cycle, expectedpoc; int i; if (sps->poc_cycle_length != 0) abs_frame_num = pc->frame_num_offset + pc->frame_num; else abs_frame_num = 0; if (nal_ref_idc == 0 && abs_frame_num > 0) abs_frame_num--; expected_delta_per_poc_cycle = 0; for (i = 0; i < sps->poc_cycle_length; i++) // FIXME integrate during sps parse expected_delta_per_poc_cycle += sps->offset_for_ref_frame[i]; if (abs_frame_num > 0) { int poc_cycle_cnt = (abs_frame_num - 1) / sps->poc_cycle_length; int frame_num_in_poc_cycle = (abs_frame_num - 1) % sps->poc_cycle_length; expectedpoc = poc_cycle_cnt * expected_delta_per_poc_cycle; for (i = 0; i <= frame_num_in_poc_cycle; i++) expectedpoc = expectedpoc + sps->offset_for_ref_frame[i]; } else expectedpoc = 0; if (nal_ref_idc == 0) expectedpoc = expectedpoc + sps->offset_for_non_ref_pic; field_poc[0] = expectedpoc + pc->delta_poc[0]; field_poc[1] = field_poc[0] + sps->offset_for_top_to_bottom_field; if (picture_structure == PICT_FRAME) field_poc[1] += pc->delta_poc[1]; } else { int poc = 2 * (pc->frame_num_offset + pc->frame_num); if (!nal_ref_idc) poc--; field_poc[0] = poc; field_poc[1] = poc; } if (picture_structure != PICT_BOTTOM_FIELD) pic_field_poc[0] = field_poc[0]; if (picture_structure != PICT_TOP_FIELD) pic_field_poc[1] = field_poc[1]; *pic_poc = FFMIN(pic_field_poc[0], pic_field_poc[1]); return 0; }