libavcodec/utils.c File Reference

utils. More...

#include "libavutil/avstring.h"
#include "libavutil/integer.h"
#include "libavutil/crc.h"
#include "libavutil/pixdesc.h"
#include "avcodec.h"
#include "dsputil.h"
#include "opt.h"
#include "imgconvert.h"
#include "audioconvert.h"
#include "libxvid_internal.h"
#include "internal.h"
#include <stdlib.h>
#include <stdarg.h>
#include <limits.h>
#include <float.h>
#include <fcntl.h>

Go to the source code of this file.

Data Structures

struct  InternalBuffer
struct  VideoFrameSizeAbbr
struct  VideoFrameRateAbbr

Defines

#define _XOPEN_SOURCE   600
#define INTERNAL_BUFFER_SIZE   32
#define SANE_NB_CHANNELS   128U
#define LICENSE_PREFIX   "libavcodec license: "

Functions

void * av_fast_realloc (void *ptr, unsigned int *size, unsigned int min_size)
 Reallocates the given block if it is not large enough, otherwise it does nothing.
void av_fast_malloc (void *ptr, unsigned int *size, unsigned int min_size)
 Allocates a buffer, reusing the given one if large enough.
AVCodec * av_codec_next (AVCodec *c)
 If c is NULL, returns the first registered codec, if c is non-NULL, returns the next registered codec after c, or NULL if c is the last one.
void avcodec_register (AVCodec *codec)
 Register the codec codec and initialize libavcodec.
void register_avcodec (AVCodec *codec)
unsigned avcodec_get_edge_width (void)
 Returns the amount of padding in pixels which the get_buffer callback must provide around the edge of the image for codecs which do not have the CODEC_FLAG_EMU_EDGE flag.
void avcodec_set_dimensions (AVCodecContext *s, int width, int height)
void avcodec_align_dimensions2 (AVCodecContext *s, int *width, int *height, int linesize_align[4])
 Modifies width and height values so that they will result in a memory buffer that is acceptable for the codec if you also ensure that all line sizes are a multiple of the respective linesize_align[i].
void avcodec_align_dimensions (AVCodecContext *s, int *width, int *height)
 Modifies width and height values so that they will result in a memory buffer that is acceptable for the codec if you do not use any horizontal padding.
int avcodec_check_dimensions (void *av_log_ctx, unsigned int w, unsigned int h)
 Checks if the given dimension of a picture is valid, meaning that all bytes of the picture can be addressed with a signed int.
int avcodec_default_get_buffer (AVCodecContext *s, AVFrame *pic)
void avcodec_default_release_buffer (AVCodecContext *s, AVFrame *pic)
int avcodec_default_reget_buffer (AVCodecContext *s, AVFrame *pic)
int avcodec_default_execute (AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
int avcodec_default_execute2 (AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int jobnr, int threadnr), void *arg, int *ret, int count)
enum PixelFormat avcodec_default_get_format (struct AVCodecContext *s, const enum PixelFormat *fmt)
void avcodec_get_frame_defaults (AVFrame *pic)
 Sets the fields of the given AVFrame to default values.
AVFrame * avcodec_alloc_frame (void)
 Allocates an AVFrame and sets its fields to default values.
int attribute_align_arg avcodec_open (AVCodecContext *avctx, AVCodec *codec)
 Initializes the AVCodecContext to use the given AVCodec.
int attribute_align_arg avcodec_encode_audio (AVCodecContext *avctx, uint8_t *buf, int buf_size, const short *samples)
 Encodes an audio frame from samples into buf.
int attribute_align_arg avcodec_encode_video (AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVFrame *pict)
 Encodes a video frame from pict into buf.
int avcodec_encode_subtitle (AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVSubtitle *sub)
int attribute_align_arg avcodec_decode_video (AVCodecContext *avctx, AVFrame *picture, int *got_picture_ptr, const uint8_t *buf, int buf_size)
 Decodes a video frame from buf into picture.
int attribute_align_arg avcodec_decode_video2 (AVCodecContext *avctx, AVFrame *picture, int *got_picture_ptr, AVPacket *avpkt)
 Decodes the video frame of size avpkt->size from avpkt->data into picture.
int attribute_align_arg avcodec_decode_audio2 (AVCodecContext *avctx, int16_t *samples, int *frame_size_ptr, const uint8_t *buf, int buf_size)
 Decodes an audio frame from buf into samples.
int attribute_align_arg avcodec_decode_audio3 (AVCodecContext *avctx, int16_t *samples, int *frame_size_ptr, AVPacket *avpkt)
 Decodes the audio frame of size avpkt->size from avpkt->data into samples.
int avcodec_decode_subtitle (AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, const uint8_t *buf, int buf_size)
int avcodec_decode_subtitle2 (AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, AVPacket *avpkt)
 Decodes a subtitle message.
av_cold int avcodec_close (AVCodecContext *avctx)
AVCodec * avcodec_find_encoder (enum CodecID id)
 Finds a registered encoder with a matching codec ID.
AVCodec * avcodec_find_encoder_by_name (const char *name)
 Finds a registered encoder with the specified name.
AVCodec * avcodec_find_decoder (enum CodecID id)
 Finds a registered decoder with a matching codec ID.
AVCodec * avcodec_find_decoder_by_name (const char *name)
 Finds a registered decoder with the specified name.
static int get_bit_rate (AVCodecContext *ctx)
void avcodec_string (char *buf, int buf_size, AVCodecContext *enc, int encode)
unsigned avcodec_version (void)
 Returns the LIBAVCODEC_VERSION_INT constant.
const char * avcodec_configuration (void)
 Returns the libavcodec build-time configuration.
const char * avcodec_license (void)
 Returns the libavcodec license.
void avcodec_init (void)
 Initializes libavcodec.
void avcodec_flush_buffers (AVCodecContext *avctx)
 Flush buffers, should be called when seeking or when switching to a different stream.
void avcodec_default_free_buffers (AVCodecContext *s)
char av_get_pict_type_char (int pict_type)
 Returns a single letter to describe the given picture type pict_type.
int av_get_bits_per_sample (enum CodecID codec_id)
 Returns codec bits per sample.
int av_get_bits_per_sample_format (enum SampleFormat sample_fmt)
 Returns sample format bits per sample.
int avcodec_thread_init (AVCodecContext *s, int thread_count)
unsigned int av_xiphlacing (unsigned char *s, unsigned int v)
 Encodes extradata length to a buffer.
int av_tempfile (char *prefix, char **filename)
int av_parse_video_frame_size (int *width_ptr, int *height_ptr, const char *str)
 Parses str and put in width_ptr and height_ptr the detected values.
int av_parse_video_frame_rate (AVRational *frame_rate, const char *arg)
 Parses str and put in frame_rate the detected values.
int ff_match_2uint16 (const uint16_t(*tab)[2], int size, int a, int b)
 Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
void av_log_missing_feature (void *avc, const char *feature, int want_sample)
 Logs a generic warning message about a missing feature.
void av_log_ask_for_sample (void *avc, const char *msg)
 Logs a generic warning message asking for a sample.
void av_register_hwaccel (AVHWAccel *hwaccel)
 Registers the hardware accelerator hwaccel.
AVHWAccel * av_hwaccel_next (AVHWAccel *hwaccel)
 If hwaccel is NULL, returns the first registered hardware accelerator, if hwaccel is non-NULL, returns the next registered hardware accelerator after hwaccel, or NULL if hwaccel is the last one.
AVHWAccel * ff_find_hwaccel (enum CodecID codec_id, enum PixelFormat pix_fmt)
 Returns the hardware accelerated codec for codec codec_id and pixel format pix_fmt.
int av_lockmgr_register (int(*cb)(void **mutex, enum AVLockOp op))
 Register a user provided lock manager supporting the operations specified by AVLockOp.

Variables

static int volatile entangled_thread_counter = 0
int(* ff_lockmgr_cb )(void **mutex, enum AVLockOp op)
static void * codec_mutex
static AVCodec * first_avcodec = NULL
static const VideoFrameSizeAbbr video_frame_size_abbrs []
static const VideoFrameRateAbbr video_frame_rate_abbrs []
static AVHWAccel * first_hwaccel = NULL

Detailed Description

utils.

Definition in file utils.c.

Define Documentation

#define _XOPEN_SOURCE   600

Definition at line 29 of file utils.c.

#define INTERNAL_BUFFER_SIZE   32

Definition at line 125 of file utils.c.

Referenced by avcodec_default_free_buffers(), and avcodec_default_get_buffer().

#define LICENSE_PREFIX   "libavcodec license: "

Referenced by avcodec_license(), avdevice_license(), avfilter_license(), avformat_license(), avutil_license(), postproc_license(), and swscale_license().

#define SANE_NB_CHANNELS   128U

Referenced by avcodec_open().

Function Documentation

AVCodec* av_codec_next ( AVCodec *  c  ) 

If c is NULL, returns the first registered codec, if c is non-NULL, returns the next registered codec after c, or NULL if c is the last one.

Definition at line 82 of file utils.c.

Referenced by show_codecs().

void av_fast_malloc ( void *  ptr,
unsigned int *  size,
unsigned int  min_size 
)

Allocates a buffer, reusing the given one if large enough.

Contrary to av_fast_realloc the current buffer contents might not be preserved and on error the old buffer is freed, thus no special handling to avoid memleaks is necessary.

Parameters:
ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer
size size of the buffer *ptr points to
min_size minimum size of *ptr buffer after returning, *ptr will be NULL and *size 0 if an error occurred.

Definition at line 68 of file utils.c.

Referenced by decode_frame(), decode_i_frame(), decode_p_frame(), do_audio_out(), ff_h263_decode_frame(), ff_h264_decode_nal(), ljpeg_decode_rgb_scan(), mimic_decode_frame(), mp_decode_frame(), parse_picture_segment(), spdif_write_packet(), and tqi_decode_frame().

void* av_fast_realloc ( void *  ptr,
unsigned int *  size,
unsigned int  min_size 
)

Reallocates the given block if it is not large enough, otherwise it does nothing.

See also:
av_realloc

Definition at line 54 of file utils.c.

Referenced by allocate_buffers(), av_add_index_entry(), avcodec_default_get_buffer(), commit_slices(), decode_frame(), dirac_combine_frame(), ff_combine_frame(), ff_vaapi_alloc_slice(), ff_vdpau_add_data_chunk(), flac_decode_frame(), get_stats(), read_frame(), read_header(), and shorten_decode_frame().

int av_get_bits_per_sample ( enum CodecID  codec_id  ) 

Returns codec bits per sample.

Parameters:
[in] codec_id the codec
Returns:
Number of bits per sample or zero if unknown for the given codec.

Definition at line 985 of file utils.c.

Referenced by aiff_write_header(), au_read_packet(), av_find_stream_info(), av_write_header(), do_audio_out(), ff_alsa_open(), ff_audio_interleave_init(), get_aiff_header(), get_audio_frame_size(), get_bit_rate(), gxf_packet(), mkv_write_tracks(), mov_get_codec_tag(), mov_read_stsd(), mov_write_audio_tag(), mov_write_header(), mxf_write_generic_sound_common(), pcm_decode_frame(), pcm_encode_frame(), pcm_encode_init(), show_stream(), and voc_get_packet().

int av_get_bits_per_sample_format ( enum SampleFormat  sample_fmt  ) 

Returns sample format bits per sample.

Parameters:
[in] sample_fmt the sample format
Returns:
Number of bits per sample or zero if unknown for the given sample format.

Definition at line 1030 of file utils.c.

Referenced by audio_decode_frame(), av_audio_resample_init(), decode_frame(), do_audio_out(), mkv_write_tracks(), output_packet(), and qdm2_decode_frame().

char av_get_pict_type_char ( int  pict_type  ) 

Returns a single letter to describe the given picture type pict_type.

Parameters:
[in] pict_type the picture type
Returns:
A single character representing the picture type.

Definition at line 972 of file utils.c.

Referenced by decode_slice_header(), do_video_stats(), ff_flv_decode_picture_header(), ff_h263_show_pict_info(), ff_h264_decode_mb_cavlc(), ff_rate_estimate_qscale(), output_picture2(), and svq3_decode_frame().

AVHWAccel* av_hwaccel_next ( AVHWAccel *  hwaccel  ) 

If hwaccel is NULL, returns the first registered hardware accelerator, if hwaccel is non-NULL, returns the next registered hardware accelerator after hwaccel, or NULL if hwaccel is the last one.

Definition at line 1268 of file utils.c.

Referenced by ff_find_hwaccel().

int av_lockmgr_register ( int(*)(void **mutex, enum AVLockOp op)  cb  ) 

Register a user provided lock manager supporting the operations specified by AVLockOp.

mutex points to a (void *) where the lockmgr should store/get a pointer to a user allocated mutex. It's NULL upon AV_LOCK_CREATE and != NULL for all other ops.

Parameters:
cb User defined callback. Note: FFmpeg may invoke calls to this callback during the call to av_lockmgr_register(). Thus, the application must be prepared to handle that. If cb is set to NULL the lockmgr will be unregistered. Also note that during unregistration the previously registered lockmgr callback may also be invoked.

Definition at line 1285 of file utils.c.

void av_log_ask_for_sample ( void *  avc,
const char *  msg 
)

Logs a generic warning message asking for a sample.

This function is intended to be used internally by FFmpeg (libavcodec, libavformat, etc.) only, and would normally not be used by applications.

Parameters:
[in] avc a pointer to an arbitrary struct of which the first field is a pointer to an AVClass struct
[in] msg string containing an optional message, or NULL if no message

Definition at line 1248 of file utils.c.

Referenced by av_log_missing_feature(), decode_channel_transform(), decode_frame(), decode_init(), decode_subframe(), determine_bitrate(), read_header(), and save_bits().

void av_log_missing_feature ( void *  avc,
const char *  feature,
int  want_sample 
)

Logs a generic warning message about a missing feature.

This function is intended to be used internally by FFmpeg (libavcodec, libavformat, etc.) only, and would normally not be used by applications.

Parameters:
[in] avc a pointer to an arbitrary struct of which the first field is a pointer to an AVClass struct
[in] feature string containing the name of the missing feature
[in] want_sample indicates if samples are wanted which exhibit this feature. If want_sample is non-zero, additional verbage will be added to the log message which tells the user how to report samples to the development mailing list.

Definition at line 1236 of file utils.c.

Referenced by aac_adtstoasc_filter(), amrnb_decode_frame(), asfrtp_parse_packet(), decode_audio_block(), decode_ga_specific_config(), decode_ics(), decode_ics_info(), decode_subframe(), ff_adts_decode_extradata(), ff_eac3_parse_header(), parse_adts_frame_header(), read_sbr_extension(), and synth_superframe().

int av_parse_video_frame_rate ( AVRational *  frame_rate,
const char *  str 
)

Parses str and put in frame_rate the detected values.

Returns:
0 in case of a successful parsing, a negative value otherwise
Parameters:
[in] str the string to parse: it has to be a string in the format <frame_rate_num>/<frame_rate_den>, a float number or a valid video rate abbreviation
[in,out] frame_rate pointer to the AVRational which will contain the detected frame rate

Definition at line 1192 of file utils.c.

Referenced by opt_frame_rate(), parse_ffconfig(), and parse_frame_rate().

int av_parse_video_frame_size ( int *  width_ptr,
int *  height_ptr,
const char *  str 
)

Parses str and put in width_ptr and height_ptr the detected values.

Returns:
0 in case of a successful parsing, a negative value otherwise
Parameters:
[in] str the string to parse: it has to be a string in the format <width>x<height> or a valid video frame size abbreviation.
[in,out] width_ptr pointer to the variable which will contain the detected frame width value
[in,out] height_ptr pointer to the variable which will contain the detected frame height value

Definition at line 1164 of file utils.c.

Referenced by opt_frame_size(), parse_ffconfig(), and parse_image_size().

void av_register_hwaccel ( AVHWAccel *  hwaccel  ) 

Registers the hardware accelerator hwaccel.

Definition at line 1259 of file utils.c.

int av_tempfile ( char *  prefix,
char **  filename 
)

Definition at line 1072 of file utils.c.

Referenced by ff_xvid_rate_control_init(), and xvid_encode_init().

unsigned int av_xiphlacing ( unsigned char *  s,
unsigned int  v 
)

Encodes extradata length to a buffer.

Used by xiph codecs.

Parameters:
s buffer to write to; must be at least (v/255+1) bytes long
v size of extradata in bytes
Returns:
number of bytes written to the buffer.

Definition at line 1053 of file utils.c.

Referenced by fixup_vorbis_headers(), oggvorbis_encode_init(), parse_packed_headers(), and put_main_header().

void avcodec_align_dimensions ( AVCodecContext *  s,
int *  width,
int *  height 
)

Modifies width and height values so that they will result in a memory buffer that is acceptable for the codec if you do not use any horizontal padding.

May only be used if a codec with CODEC_CAP_DR1 has been opened. If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased according to avcodec_get_edge_width() before.

Definition at line 210 of file utils.c.

void avcodec_align_dimensions2 ( AVCodecContext *  s,
int *  width,
int *  height,
int  linesize_align[4] 
)

Modifies width and height values so that they will result in a memory buffer that is acceptable for the codec if you also ensure that all line sizes are a multiple of the respective linesize_align[i].

May only be used if a codec with CODEC_CAP_DR1 has been opened. If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased according to avcodec_get_edge_width() before.

Definition at line 127 of file utils.c.

Referenced by avcodec_align_dimensions(), and avcodec_default_get_buffer().

AVFrame* avcodec_alloc_frame ( void   ) 

Allocates an AVFrame and sets its fields to default values.

The resulting struct can be deallocated by simply calling av_free().

Returns:
An AVFrame filled with default values or NULL on failure.
See also:
avcodec_get_frame_defaults

Definition at line 452 of file utils.c.

Referenced by aac_encode_init(), AC3_encode_init(), adx_encode_init(), alac_encode_init(), alloc_picture(), decode_init(), encode_init(), Faac_encode_init(), flac_encode_init(), g726_init(), libgsm_init(), MP3lame_encode_init(), MPA_encode_init(), oggvorbis_encode_init(), pcm_encode_init(), roq_dpcm_encode_init(), video_decode_example(), video_encode_example(), video_thread(), vorbis_encode_init(), and vp8_init().

int avcodec_check_dimensions ( void *  av_log_ctx,
unsigned int  w,
unsigned int  h 
)

Checks if the given dimension of a picture is valid, meaning that all bytes of the picture can be addressed with a signed int.

Parameters:
[in] w Width of the picture.
[in] h Height of the picture.
Returns:
Zero if valid, a negative value if invalid.

Definition at line 222 of file utils.c.

Referenced by avcodec_decode_video2(), avcodec_default_get_buffer(), avcodec_encode_video(), avcodec_open(), avpicture_fill(), avpicture_get_size(), cmv_decode_frame(), codec_reinit(), decode_frame(), decode_init(), dnxhd_decode_frame(), ff_dirac_parse_sequence_header(), ff_flv_decode_picture_header(), ff_h264_decode_seq_parameter_set(), ff_mjpeg_decode_sof(), ff_pnm_decode_header(), gif_decode_frame(), grab_read_header(), iv_decode_frame(), libdirac_decode_frame(), libopenjpeg_decode_frame(), libschroedinger_handle_first_access_unit(), MPV_common_init(), pcx_decode_frame(), ptx_decode_frame(), qtrle_encode_init(), rv20_decode_picture_header(), rv40_parse_slice_header(), sunrast_decode_frame(), tgv_decode_frame(), tiff_decode_tag(), txd_decode_frame(), v4l2_read_header(), vp8_decode(), vqa_decode_init(), and yop_decode_init().

av_cold int avcodec_close ( AVCodecContext *  avctx  ) 

Definition at line 692 of file utils.c.

Referenced by audio_decode_example(), audio_encode_example(), av_find_stream_info(), close_audio(), close_connection(), close_video(), estimate_best_b_count(), stream_component_close(), video_decode_example(), and video_encode_example().

const char* avcodec_configuration ( void   ) 

Returns the libavcodec build-time configuration.

Definition at line 925 of file utils.c.

Referenced by show_banner().

int attribute_align_arg avcodec_decode_audio2 ( AVCodecContext *  avctx,
int16_t *  samples,
int *  frame_size_ptr,
const uint8_t *  buf,
int  buf_size 
)

Decodes an audio frame from buf into samples.

Wrapper function which calls avcodec_decode_audio3.

Deprecated:
Use avcodec_decode_audio3 instead.
Parameters:
avctx the codec context
[out] samples the output buffer
[in,out] frame_size_ptr the output buffer size in bytes
[in] buf the input buffer
[in] buf_size the input buffer size in bytes
Returns:
On error a negative value is returned, otherwise the number of bytes used or zero if no frame could be decompressed.

Definition at line 625 of file utils.c.

int attribute_align_arg avcodec_decode_audio3 ( AVCodecContext *  avctx,
int16_t *  samples,
int *  frame_size_ptr,
AVPacket *  avpkt 
)

Decodes the audio frame of size avpkt->size from avpkt->data into samples.

Some decoders may support multiple frames in a single AVPacket, such decoders would then just decode the first frame. In this case, avcodec_decode_audio3 has to be called again with an AVPacket that contains the remaining data in order to decode the second frame etc. If no frame could be outputted, frame_size_ptr is zero. Otherwise, it is the decompressed frame size in bytes.

Warning:
You must set frame_size_ptr to the allocated size of the output buffer before calling avcodec_decode_audio3().

The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than the actual read bytes because some optimized bitstream readers read 32 or 64 bits at once and could read over the end.

The end of the input buffer avpkt->data should be set to 0 to ensure that no overreading happens for damaged MPEG streams.

Note:
You might have to align the input buffer avpkt->data and output buffer samples. The alignment requirements depend on the CPU: On some CPUs it isn't necessary at all, on others it won't work at all if not aligned and on others it will work but it will have an impact on performance.
In practice, avpkt->data should have 4 byte alignment at minimum and samples should be 16 byte aligned unless the CPU doesn't need it (AltiVec and SSE do).

Parameters:
avctx the codec context
[out] samples the output buffer, sample type in avctx->sample_fmt
[in,out] frame_size_ptr the output buffer size in bytes
[in] avpkt The input AVPacket containing the input buffer. You can create such packet with av_init_packet() and by then setting data and size, some decoders might in addition need other fields. All decoders are designed to use the least fields possible though.
Returns:
On error a negative value is returned, otherwise the number of bytes used or zero if no frame data was decompressed (used) from the input AVPacket.

Definition at line 638 of file utils.c.

Referenced by audio_decode_example(), audio_decode_frame(), avcodec_decode_audio2(), output_packet(), and try_decode_frame().

int avcodec_decode_subtitle ( AVCodecContext *  avctx,
AVSubtitle *  sub,
int *  got_sub_ptr,
const uint8_t *  buf,
int  buf_size 
)

Definition at line 666 of file utils.c.

int avcodec_decode_subtitle2 ( AVCodecContext *  avctx,
AVSubtitle *  sub,
int *  got_sub_ptr,
AVPacket *  avpkt 
)

Decodes a subtitle message.

Returns a negative value on error, otherwise returns the number of bytes used. If no subtitle could be decompressed, got_sub_ptr is zero. Otherwise, the subtitle is stored in *sub.

Parameters:
avctx the codec context
[out] sub The AVSubtitle in which the decoded subtitle will be stored.
[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
[in] avpkt The input AVPacket containing the input buffer.

Definition at line 679 of file utils.c.

Referenced by avcodec_decode_subtitle(), output_packet(), and subtitle_thread().

int attribute_align_arg avcodec_decode_video ( AVCodecContext *  avctx,
AVFrame *  picture,
int *  got_picture_ptr,
const uint8_t *  buf,
int  buf_size 
)

Decodes a video frame from buf into picture.

Wrapper function which calls avcodec_decode_video2.

Deprecated:
Use avcodec_decode_video2 instead.
Parameters:
avctx the codec context
[out] picture The AVFrame in which the decoded video frame will be stored.
[in] buf the input buffer
[in] buf_size the size of the input buffer in bytes
[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
Returns:
On error a negative value is returned, otherwise the number of bytes used or zero if no frame could be decompressed.

Definition at line 586 of file utils.c.

int attribute_align_arg avcodec_decode_video2 ( AVCodecContext *  avctx,
AVFrame *  picture,
int *  got_picture_ptr,
AVPacket *  avpkt 
)

Decodes the video frame of size avpkt->size from avpkt->data into picture.

Some decoders may support multiple frames in a single AVPacket, such decoders would then just decode the first frame.

Warning:
The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than the actual read bytes because some optimized bitstream readers read 32 or 64 bits at once and could read over the end.

The end of the input buffer buf should be set to 0 to ensure that no overreading happens for damaged MPEG streams.

Note:
You might have to align the input buffer avpkt->data. The alignment requirements depend on the CPU: on some CPUs it isn't necessary at all, on others it won't work at all if not aligned and on others it will work but it will have an impact on performance.
In practice, avpkt->data should have 4 byte alignment at minimum.

Note:
Some codecs have a delay between input and output, these need to be fed with avpkt->data=NULL, avpkt->size=0 at the end to return the remaining frames.
Parameters:
avctx the codec context
[out] picture The AVFrame in which the decoded video frame will be stored. Use avcodec_alloc_frame to get an AVFrame, the codec will allocate memory for the actual bitmap.
[in] avpkt The input AVpacket containing the input buffer. You can create such packet with av_init_packet() and by then setting data and size, some decoders might in addition need other fields like flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least fields possible.
[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
Returns:
On error a negative value is returned, otherwise the number of bytes used or zero if no frame could be decompressed.

Definition at line 601 of file utils.c.

Referenced by avcodec_decode_video(), get_video_frame(), output_packet(), try_decode_frame(), and video_decode_example().

int avcodec_default_execute ( AVCodecContext *  c,
int(*)(AVCodecContext *c2, void *arg2)  func,
void *  arg,
int *  ret,
int  count,
int  size 
)

Definition at line 419 of file utils.c.

Referenced by avcodec_get_context_defaults2().

int avcodec_default_execute2 ( AVCodecContext *  c,
int(*)(AVCodecContext *c2, void *arg2, int jobnr, int threadnr)  func,
void *  arg,
int *  ret,
int  count 
)

Definition at line 429 of file utils.c.

void avcodec_default_free_buffers ( AVCodecContext *  s  ) 

Definition at line 953 of file utils.c.

Referenced by avcodec_close(), and MPV_common_end().

int avcodec_default_get_buffer ( AVCodecContext *  s,
AVFrame *  pic 
)

Definition at line 230 of file utils.c.

Referenced by avcodec_get_context_defaults2().

enum PixelFormat avcodec_default_get_format ( struct AVCodecContext *  s,
const enum PixelFormat *  fmt 
)

Definition at line 439 of file utils.c.

Referenced by avcodec_get_context_defaults2().

int avcodec_default_reget_buffer ( AVCodecContext *  s,
AVFrame *  pic 
)

Definition at line 385 of file utils.c.

Referenced by avcodec_get_context_defaults2().

void avcodec_default_release_buffer ( AVCodecContext *  s,
AVFrame *  pic 
)

Definition at line 356 of file utils.c.

Referenced by avcodec_get_context_defaults2().

int attribute_align_arg avcodec_encode_audio ( AVCodecContext *  avctx,
uint8_t *  buf,
int  buf_size,
const short *  samples 
)

Encodes an audio frame from samples into buf.

Note:
The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large. However, for PCM audio the user will know how much space is needed because it depends on the value passed in buf_size as described below. In that case a lower value can be used.
Parameters:
avctx the codec context
[out] buf the output buffer
[in] buf_size the output buffer size
[in] samples the input buffer containing the samples The number of samples read from this buffer is frame_size*channels, both of which are defined in avctx. For PCM audio the number of samples read from samples is equal to buf_size * input_sample_size / output_sample_size.
Returns:
On error a negative value is returned, on success zero or the number of bytes used to encode the data read from the input buffer.

Definition at line 536 of file utils.c.

Referenced by audio_encode_example(), do_audio_out(), output_packet(), and write_audio_frame().

int avcodec_encode_subtitle ( AVCodecContext *  avctx,
uint8_t *  buf,
int  buf_size,
const AVSubtitle *  sub 
)

Definition at line 570 of file utils.c.

Referenced by do_subtitle_out().

int attribute_align_arg avcodec_encode_video ( AVCodecContext *  avctx,
uint8_t *  buf,
int  buf_size,
const AVFrame *  pict 
)

Encodes a video frame from pict into buf.

The input picture should be stored using a specific format, namely avctx.pix_fmt.

Parameters:
avctx the codec context
[out] buf the output buffer for the bitstream of encoded frame
[in] buf_size the size of the output buffer in bytes
[in] pict the input picture to encode
Returns:
On error a negative value is returned, on success zero or the number of bytes used from the output buffer.

Definition at line 551 of file utils.c.

Referenced by do_video_out(), estimate_best_b_count(), output_packet(), video_encode_example(), and write_video_frame().

AVCodec* avcodec_find_decoder ( enum CodecID  id  ) 

Finds a registered decoder with a matching codec ID.

Parameters:
id CodecID of the requested decoder
Returns:
A decoder if one was found, NULL otherwise.

Definition at line 755 of file utils.c.

Referenced by audio_decode_example(), av_find_stream_info(), av_transcode(), avcodec_string(), find_codec_or_die(), open_input_file(), open_parser(), sdp_parse_rtpmap(), stream_component_open(), try_decode_frame(), and video_decode_example().

AVCodec* avcodec_find_decoder_by_name ( const char *  name  ) 

Finds a registered decoder with the specified name.

Parameters:
name name of the requested decoder
Returns:
A decoder if one was found, NULL otherwise.

Definition at line 767 of file utils.c.

Referenced by find_codec_or_die(), and opt_input_file().

AVCodec* avcodec_find_encoder ( enum CodecID  id  ) 

Finds a registered encoder with a matching codec ID.

Parameters:
id CodecID of the requested encoder
Returns:
An encoder if one was found, NULL otherwise.

Definition at line 725 of file utils.c.

Referenced by asf_write_header1(), audio_encode_example(), av_transcode(), avcodec_string(), compute_status(), estimate_best_b_count(), find_codec_or_die(), new_audio_stream(), new_video_stream(), open_audio(), open_video(), read_ffserver_streams(), and video_encode_example().

AVCodec* avcodec_find_encoder_by_name ( const char *  name  ) 

Finds a registered encoder with the specified name.

Parameters:
name name of the requested encoder
Returns:
An encoder if one was found, NULL otherwise.

Definition at line 741 of file utils.c.

Referenced by find_codec_or_die(), new_audio_stream(), new_subtitle_stream(), new_video_stream(), opt_audio_codec(), and opt_video_codec().

void avcodec_flush_buffers ( AVCodecContext *  avctx  ) 

Flush buffers, should be called when seeking or when switching to a different stream.

Definition at line 947 of file utils.c.

Referenced by audio_decode_frame(), get_video_frame(), and subtitle_thread().

unsigned avcodec_get_edge_width ( void   ) 

Returns the amount of padding in pixels which the get_buffer callback must provide around the edge of the image for codecs which do not have the CODEC_FLAG_EMU_EDGE flag.

Returns:
Required padding in pixels.

Definition at line 104 of file utils.c.

void avcodec_get_frame_defaults ( AVFrame *  pic  ) 

Sets the fields of the given AVFrame to default values.

Parameters:
pic The AVFrame of which the fields should be set to default values.

Definition at line 445 of file utils.c.

Referenced by av_transcode(), avcodec_alloc_frame(), bmp_decode_init(), bmp_encode_init(), cdg_init_frame(), decode_init(), do_video_out(), encode_init(), estimate_best_b_count(), ff_pnm_init(), gif_decode_init(), MPV_common_init(), output_packet(), pcx_encode_init(), pcx_init(), png_dec_init(), png_enc_init(), ptx_init(), sgi_init(), sunrast_init(), targa_encode_init(), targa_init(), tiff_init(), try_decode_frame(), and txd_init().

void avcodec_init ( void   ) 

Initializes libavcodec.

Warning:
This function must be called before any other libavcodec function.

Definition at line 936 of file utils.c.

Referenced by avcodec_register(), and main().

const char* avcodec_license ( void   ) 

Returns the libavcodec license.

Definition at line 930 of file utils.c.

int attribute_align_arg avcodec_open ( AVCodecContext *  avctx,
AVCodec *  codec 
)

Initializes the AVCodecContext to use the given AVCodec.

Prior to using this function the context has to be allocated.

The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(), avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for retrieving a codec.

Warning:
This function is not thread safe!
 avcodec_register_all();
 codec = avcodec_find_decoder(CODEC_ID_H264);
 if (!codec)
     exit(1);

 context = avcodec_alloc_context();

 if (avcodec_open(context, codec) < 0)
     exit(1);

Parameters:
avctx The context which will be set up to use the given codec.
codec The codec to use within the context.
Returns:
zero on success, a negative value on error
See also:
avcodec_alloc_context, avcodec_find_decoder, avcodec_find_encoder

Definition at line 462 of file utils.c.

Referenced by audio_decode_example(), audio_encode_example(), av_find_stream_info(), av_transcode(), estimate_best_b_count(), open_audio(), open_input_file(), open_parser(), open_video(), stream_component_open(), try_decode_frame(), video_decode_example(), and video_encode_example().

void avcodec_register ( AVCodec *  codec  ) 

Register the codec codec and initialize libavcodec.

See also:
avcodec_init()

Definition at line 87 of file utils.c.

Referenced by register_avcodec().

void avcodec_set_dimensions ( AVCodecContext *  s,
int  width,
int  height 
)

Definition at line 109 of file utils.c.

Referenced by av_mpeg4_decode_header(), avcodec_open(), cmv_process_header(), decode_frame(), decode_slice_header(), dnxhd_decode_frame(), ff_dirac_parse_sequence_header(), ff_h263_decode_frame(), ff_mjpeg_decode_sof(), gif_decode_frame(), h261_decode_frame(), iv_decode_frame(), libopenjpeg_decode_frame(), mpeg_decode_postinit(), mpegvideo_extract_headers(), pcx_decode_frame(), ptx_decode_frame(), rv20_decode_picture_header(), rv34_decode_slice(), sunrast_decode_frame(), svq1_decode_frame(), tgq_decode_frame(), tgv_decode_frame(), theora_header(), tiff_decode_tag(), tqi_decode_frame(), txd_decode_frame(), vp5_parse_header(), vp6_parse_header(), and vp8_decode().

void avcodec_string ( char *  buf,
int  buf_size,
AVCodecContext *  enc,
int  encode 
)

Definition at line 804 of file utils.c.

Referenced by av_find_stream_info(), and dump_stream_format().

int avcodec_thread_init ( AVCodecContext *  s,
int  thread_count 
)

Definition at line 1047 of file utils.c.

unsigned avcodec_version ( void   ) 

Returns the LIBAVCODEC_VERSION_INT constant.

Definition at line 920 of file utils.c.

AVHWAccel* ff_find_hwaccel ( enum CodecID  codec_id,
enum PixelFormat  pix_fmt 
)

Returns the hardware accelerated codec for codec codec_id and pixel format pix_fmt.

Parameters:
codec_id the codec to match
pix_fmt the pixel format to match
Returns:
the hardware accelerated codec, or NULL if none was found.

Definition at line 1273 of file utils.c.

Referenced by decode_slice_header(), ff_h263_decode_init(), vc1_decode_init(), and vcr2_init_sequence().

int ff_match_2uint16 ( const uint16_t(*)  tab[2],
int  size,
int  a,
int  b 
)

Return the index into tab at which {a,b} match elements {[0],[1]} of tab.

If there is no such matching pair then size is returned.

Definition at line 1230 of file utils.c.

Referenced by h263_encode_picture_header(), MPV_encode_init(), and svq1_write_header().

static int get_bit_rate ( AVCodecContext *  ctx  )  [static]

Definition at line 781 of file utils.c.

Referenced by avcodec_string().

void register_avcodec ( AVCodec *  codec  ) 

Deprecated:
Deprecated in favor of avcodec_register().

Definition at line 98 of file utils.c.

Variable Documentation

void* codec_mutex [static]

Definition at line 52 of file utils.c.

Referenced by av_lockmgr_register(), avcodec_close(), and avcodec_open().

int volatile entangled_thread_counter = 0 [static]

Definition at line 50 of file utils.c.

Referenced by avcodec_close(), and avcodec_open().

int(* ff_lockmgr_cb)(void **mutex, enum AVLockOp op)

Referenced by av_lockmgr_register(), avcodec_close(), and avcodec_open().

AVCodec* first_avcodec = NULL [static]

Definition at line 80 of file utils.c.

AVHWAccel* first_hwaccel = NULL [static]

Definition at line 1257 of file utils.c.

const VideoFrameRateAbbr video_frame_rate_abbrs[] [static]

Initial value:

 {
    { "ntsc",      30000, 1001 },
    { "pal",          25,    1 },
    { "qntsc",     30000, 1001 }, 
    { "qpal",         25,    1 }, 
    { "sntsc",     30000, 1001 }, 
    { "spal",         25,    1 }, 
    { "film",         24,    1 },
    { "ntsc-film", 24000, 1001 },
}

Definition at line 1153 of file utils.c.

const VideoFrameSizeAbbr video_frame_size_abbrs[] [static]

Definition at line 1113 of file utils.c.

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