tor-browser

codec_par.h (6916B)

---

/*
* Codec parameters public API
*
* 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
*/

#ifndef AVCODEC_CODEC_PAR_H
#define AVCODEC_CODEC_PAR_H

#include <stdint.h>

#include "libavutil/avutil.h"
#include "libavutil/rational.h"
#include "libavutil/pixfmt.h"

#include "codec_id.h"

/**
* @addtogroup lavc_core
*/

enum AVFieldOrder {
 AV_FIELD_UNKNOWN,
 AV_FIELD_PROGRESSIVE,
 AV_FIELD_TT,  //< Top coded_first, top displayed first
 AV_FIELD_BB,  //< Bottom coded first, bottom displayed first
 AV_FIELD_TB,  //< Top coded first, bottom displayed first
 AV_FIELD_BT,  //< Bottom coded first, top displayed first
};

/**
* This struct describes the properties of an encoded stream.
*
* sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
* be allocated with avcodec_parameters_alloc() and freed with
* avcodec_parameters_free().
*/
typedef struct AVCodecParameters {
 /**
  * General type of the encoded data.
  */
 enum AVMediaType codec_type;
 /**
  * Specific type of the encoded data (the codec used).
  */
 enum AVCodecID codec_id;
 /**
  * Additional information about the codec (corresponds to the AVI FOURCC).
  */
 uint32_t codec_tag;

 /**
  * Extra binary data needed for initializing the decoder, codec-dependent.
  *
  * Must be allocated with av_malloc() and will be freed by
  * avcodec_parameters_free(). The allocated size of extradata must be at
  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
  * bytes zeroed.
  */
 uint8_t* extradata;
 /**
  * Size of the extradata content in bytes.
  */
 int extradata_size;

 /**
  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
  */
 int format;

 /**
  * The average bitrate of the encoded data (in bits per second).
  */
 int64_t bit_rate;

 /**
  * The number of bits per sample in the codedwords.
  *
  * This is basically the bitrate per sample. It is mandatory for a bunch of
  * formats to actually decode them. It's the number of bits for one sample in
  * the actual coded bitstream.
  *
  * This could be for example 4 for ADPCM
  * For PCM formats this matches bits_per_raw_sample
  * Can be 0
  */
 int bits_per_coded_sample;

 /**
  * This is the number of valid bits in each output sample. If the
  * sample format has more bits, the least significant bits are additional
  * padding bits, which are always 0. Use right shifts to reduce the sample
  * to its actual size. For example, audio formats with 24 bit samples will
  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
  * To get the original sample use "(int32_t)sample >> 8"."
  *
  * For ADPCM this might be 12 or 16 or similar
  * Can be 0
  */
 int bits_per_raw_sample;

 /**
  * Codec-specific bitstream restrictions that the stream conforms to.
  */
 int profile;
 int level;

 /**
  * Video only. The dimensions of the video frame in pixels.
  */
 int width;
 int height;

 /**
  * Video only. The aspect ratio (width / height) which a single pixel
  * should have when displayed.
  *
  * When the aspect ratio is unknown / undefined, the numerator should be
  * set to 0 (the denominator may have any value).
  */
 AVRational sample_aspect_ratio;

 /**
  * Video only. The order of the fields in interlaced video.
  */
 enum AVFieldOrder field_order;

 /**
  * Video only. Additional colorspace characteristics.
  */
 enum AVColorRange color_range;
 enum AVColorPrimaries color_primaries;
 enum AVColorTransferCharacteristic color_trc;
 enum AVColorSpace color_space;
 enum AVChromaLocation chroma_location;

 /**
  * Video only. Number of delayed frames.
  */
 int video_delay;

 /**
  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
  * unknown or unspecified, otherwise the number of bits set must be equal to
  * the channels field.
  */
 uint64_t channel_layout;
 /**
  * Audio only. The number of audio channels.
  */
 int channels;
 /**
  * Audio only. The number of audio samples per second.
  */
 int sample_rate;
 /**
  * Audio only. The number of bytes per coded audio frame, required by some
  * formats.
  *
  * Corresponds to nBlockAlign in WAVEFORMATEX.
  */
 int block_align;
 /**
  * Audio only. Audio frame size, if known. Required by some formats to be
  * static.
  */
 int frame_size;

 /**
  * Audio only. The amount of padding (in samples) inserted by the encoder at
  * the beginning of the audio. I.e. this number of leading decoded samples
  * must be discarded by the caller to get the original audio without leading
  * padding.
  */
 int initial_padding;
 /**
  * Audio only. The amount of padding (in samples) appended by the encoder to
  * the end of the audio. I.e. this number of decoded samples must be
  * discarded by the caller from the end of the stream to get the original
  * audio without any trailing padding.
  */
 int trailing_padding;
 /**
  * Audio only. Number of samples to skip after a discontinuity.
  */
 int seek_preroll;
} AVCodecParameters;

/**
* Allocate a new AVCodecParameters and set its fields to default values
* (unknown/invalid/0). The returned struct must be freed with
* avcodec_parameters_free().
*/
AVCodecParameters* avcodec_parameters_alloc(void);

/**
* Free an AVCodecParameters instance and everything associated with it and
* write NULL to the supplied pointer.
*/
void avcodec_parameters_free(AVCodecParameters** par);

/**
* Copy the contents of src to dst. Any allocated fields in dst are freed and
* replaced with newly allocated duplicates of the corresponding fields in src.
*
* @return >= 0 on success, a negative AVERROR code on failure.
*/
int avcodec_parameters_copy(AVCodecParameters* dst,
                           const AVCodecParameters* src);

/**
* This function is the same as av_get_audio_frame_duration(), except it works
* with AVCodecParameters instead of an AVCodecContext.
*/
int av_get_audio_frame_duration2(AVCodecParameters* par, int frame_bytes);

/**
* @}
*/

#endif  // AVCODEC_CODEC_PAR_H