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/*
* CEA-708 Closed Captioning FIFO
* Copyright (c) 2023 LTN Global Communications
*
* Author: Devin Heitmueller <dheitmueller@ltnglobal.com>
*
* 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
*/
/**
* @file
* CC FIFO Buffer
*/
#ifndef AVFILTER_CCFIFO_H
#define AVFILTER_CCFIFO_H
#include "libavutil/avutil.h"
#include "libavutil/frame.h"
#include "libavutil/fifo.h"
typedef struct CCFifo {
AVFifo *cc_608_fifo;
AVFifo *cc_708_fifo;
AVRational framerate;
int expected_cc_count;
int expected_608;
int cc_detected;
int passthrough;
int passthrough_warning;
void *log_ctx;
} CCFifo;
/**
* Initialize a CCFifo.
*
* @param framerate output framerate
* @param log_ctx used for any av_log() calls
* @return Zero on success, or negative AVERROR code on failure.
*/
int ff_ccfifo_init(CCFifo *ccf, AVRational framerate, void *log_ctx);
/**
* Free all memory allocated in a CCFifo and clear the context.
*
* @param ccf Pointer to the CCFifo which should be uninitialized
*/
void ff_ccfifo_uninit(CCFifo *ccf);
/**
* Extract CC data from an AVFrame
*
* Extract CC bytes from the AVFrame, insert them into our queue, and
* remove the side data from the AVFrame. The side data is removed
* as it will be re-inserted at the appropriate rate later in the
* filter.
*
* @param af CCFifo to write to
* @param frame AVFrame with the video frame to operate on
* @return Zero on success, or negative AVERROR
* code on failure.
*/
int ff_ccfifo_extract(CCFifo *ccf, AVFrame *frame);
/**
*Just like ff_ccfifo_extract(), but takes the raw bytes instead of an AVFrame
*/
int ff_ccfifo_extractbytes(CCFifo *ccf, uint8_t *data, size_t len);
/**
* Provide the size in bytes of an output buffer to allocate
*
* Ask for how many bytes the output will contain, so the caller can allocate
* an appropriately sized buffer and pass it to ff_ccfifo_injectbytes()
*
*/
int ff_ccfifo_getoutputsize(const CCFifo *ccf);
/**
* Insert CC data from the FIFO into an AVFrame (as side data)
*
* Dequeue the appropriate number of CC tuples based on the
* frame rate, and insert them into the AVFrame
*
* @param af CCFifo to read from
* @param frame AVFrame with the video frame to operate on
* @return Zero on success, or negative AVERROR
* code on failure.
*/
int ff_ccfifo_inject(CCFifo *ccf, AVFrame *frame);
/**
* Just like ff_ccfifo_inject(), but takes the raw bytes to insert the CC data
* int rather than an AVFrame
*/
int ff_ccfifo_injectbytes(CCFifo *ccf, uint8_t *data, size_t len);
/**
* Returns 1 if captions have been found as a prior call
* to ff_ccfifo_extract() or ff_ccfifo_extractbytes()
*/
int ff_ccfifo_ccdetected(const CCFifo *ccf);
#endif /* AVFILTER_CCFIFO_H */