| /* |
| * 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(EINVAL); |
| |
| 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(EINVAL); |
| |
| new_size = (old_size + cc_count * 3); |
| |
| if (new_size > INT_MAX) |
| return AVERROR(EINVAL); |
| |
| /* 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; |
| } |