2 * CEA-708 Closed Captioning FIFO
3 * Copyright (c) 2023 LTN Global Communications
5 * Author: Devin Heitmueller <dheitmueller@ltnglobal.com>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 #ifndef AVFILTER_CCFIFO_H
30 #define AVFILTER_CCFIFO_H
32 #include "libavutil/avutil.h"
33 #include "libavutil/frame.h"
34 #include "libavutil/fifo.h"
36 typedef struct CCFifo {
40 int expected_cc_count;
44 int passthrough_warning;
49 * Initialize a CCFifo.
51 * @param framerate output framerate
52 * @param log_ctx used for any av_log() calls
53 * @return Zero on success, or negative AVERROR code on failure.
55 int ff_ccfifo_init(CCFifo *ccf, AVRational framerate, void *log_ctx);
58 * Free all memory allocated in a CCFifo and clear the context.
60 * @param ccf Pointer to the CCFifo which should be uninitialized
62 void ff_ccfifo_uninit(CCFifo *ccf);
65 * Extract CC data from an AVFrame
67 * Extract CC bytes from the AVFrame, insert them into our queue, and
68 * remove the side data from the AVFrame. The side data is removed
69 * as it will be re-inserted at the appropriate rate later in the
72 * @param af CCFifo to write to
73 * @param frame AVFrame with the video frame to operate on
74 * @return Zero on success, or negative AVERROR
77 int ff_ccfifo_extract(CCFifo *ccf, AVFrame *frame);
80 *Just like ff_ccfifo_extract(), but takes the raw bytes instead of an AVFrame
82 int ff_ccfifo_extractbytes(CCFifo *ccf, uint8_t *data, size_t len);
85 * Provide the size in bytes of an output buffer to allocate
87 * Ask for how many bytes the output will contain, so the caller can allocate
88 * an appropriately sized buffer and pass it to ff_ccfifo_injectbytes()
91 int ff_ccfifo_getoutputsize(const CCFifo *ccf);
94 * Insert CC data from the FIFO into an AVFrame (as side data)
96 * Dequeue the appropriate number of CC tuples based on the
97 * frame rate, and insert them into the AVFrame
99 * @param af CCFifo to read from
100 * @param frame AVFrame with the video frame to operate on
101 * @return Zero on success, or negative AVERROR
104 int ff_ccfifo_inject(CCFifo *ccf, AVFrame *frame);
107 * Just like ff_ccfifo_inject(), but takes the raw bytes to insert the CC data
108 * int rather than an AVFrame
110 int ff_ccfifo_injectbytes(CCFifo *ccf, uint8_t *data, size_t len);
113 * Returns 1 if captions have been found as a prior call
114 * to ff_ccfifo_extract() or ff_ccfifo_extractbytes()
116 int ff_ccfifo_ccdetected(const CCFifo *ccf);
118 #endif /* AVFILTER_CCFIFO_H */