/* * 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 <stddef.h> #include <stdint.h> #include "atsc_a53.h" #include "get_bits.h" int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len, void **data, size_t *sei_size) { AVFrameSideData *side_data = NULL; uint8_t *sei_data; if (frame) side_data = av_frame_get_side_data(frame, AV_FRAME_DATA_A53_CC); if (!side_data) { *data = NULL; return 0; } *sei_size = side_data->size + 11; *data = av_mallocz(*sei_size + prefix_len); if (!*data) return AVERROR(ENOMEM); sei_data = (uint8_t*)*data + prefix_len; // country code sei_data[0] = 181; sei_data[1] = 0; sei_data[2] = 49; /** * 'GA94' is standard in North America for ATSC, but hard coding * this style may not be the right thing to do -- other formats * do exist. This information is not available in the side_data * so we are going with this right now. */ AV_WL32(sei_data + 3, MKTAG('G', 'A', '9', '4')); sei_data[7] = 3; sei_data[8] = ((side_data->size/3) & 0x1f) | 0x40; sei_data[9] = 0; memcpy(sei_data + 10, side_data->data, side_data->size); sei_data[side_data->size+10] = 255; return 0; } int ff_parse_a53_cc(AVBufferRef **pbuf, const uint8_t *data, int size) { AVBufferRef *buf = *pbuf; GetBitContext gb; size_t new_size, old_size = buf ? buf->size : 0; int ret, cc_count; if (size < 3) return AVERROR_INVALIDDATA; ret = init_get_bits8(&gb, data, size); if (ret < 0) return ret; if (get_bits(&gb, 8) != 0x3) // user_data_type_code return 0; skip_bits(&gb, 1); // reserved if (!get_bits(&gb, 1)) // process_cc_data_flag return 0; skip_bits(&gb, 1); // zero bit cc_count = get_bits(&gb, 5); if (!cc_count) return 0; skip_bits(&gb, 8); // reserved /* 3 bytes per CC plus one byte marker_bits at the end */ if (cc_count * 3 >= (get_bits_left(&gb) >> 3)) return AVERROR_INVALIDDATA; new_size = (old_size + cc_count * 3); if (new_size > INT_MAX) return AVERROR_INVALIDDATA; /* Allow merging of the cc data from two fields. */ ret = av_buffer_realloc(pbuf, new_size); if (ret < 0) return ret; buf = *pbuf; /* Use of av_buffer_realloc assumes buffer is writeable */ for (int i = 0; i < cc_count; i++) { buf->data[old_size++] = get_bits(&gb, 8); buf->data[old_size++] = get_bits(&gb, 8); buf->data[old_size++] = get_bits(&gb, 8); } return cc_count; }