From e481458bc308ee838deaeacac51929514762e7a7 Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Mon, 21 Mar 2016 16:14:31 +0100 Subject: h264: factor out pred weight table parsing into a separate file This will allow decoupling the parser from the decoder. --- libavcodec/h264_parse.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) create mode 100644 libavcodec/h264_parse.c (limited to 'libavcodec/h264_parse.c') diff --git a/libavcodec/h264_parse.c b/libavcodec/h264_parse.c new file mode 100644 index 0000000000..88caa48f19 --- /dev/null +++ b/libavcodec/h264_parse.c @@ -0,0 +1,86 @@ +/* + * 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; +} -- cgit v1.2.3