FFmpeg: libavcodec/dv_profile.h Source File

FFmpeg

libavcodec

dv_profile.h

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1 /*

2 * This file is part of FFmpeg.

3 *

4 * FFmpeg is free software; you can redistribute it and/or

5 * modify it under the terms of the GNU Lesser General Public

6 * License as published by the Free Software Foundation; either

7 * version 2.1 of the License, or (at your option) any later version.

8 *

9 * FFmpeg is distributed in the hope that it will be useful,

10 * but WITHOUT ANY WARRANTY; without even the implied warranty of

11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

12 * Lesser General Public License for more details.

13 *

14 * You should have received a copy of the GNU Lesser General Public

15 * License along with FFmpeg; if not, write to the Free Software

16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

17 */

18

19 #ifndef AVCODEC_DV_PROFILE_H

20 #define AVCODEC_DV_PROFILE_H

21

22 #include <stdint.h>

23

24 #include "libavutil/pixfmt.h"

25 #include "libavutil/rational.h"

26

27 /* minimum number of bytes to read from a DV stream in order to

28 * determine the profile */

29 #define DV_PROFILE_BYTES (6 * 80) /* 6 DIF blocks */

30

31

32 /*

33 * AVDVProfile is used to express the differences between various

34 * DV flavors. For now it's primarily used for differentiating

35 * 525/60 and 625/50, but the plans are to use it for various

36 * DV specs as well (e.g. SMPTE314M vs. IEC 61834).

37 */

38 typedef struct AVDVProfile {

39 int dsf; /* value of the dsf in the DV header */

40 int video_stype; /* stype for VAUX source pack */

41 int frame_size; /* total size of one frame in bytes */

42 int difseg_size; /* number of DIF segments per DIF channel */

43 int n_difchan; /* number of DIF channels per frame */

44 AVRational time_base; /* 1/framerate */

45 int ltc_divisor; /* FPS from the LTS standpoint */

46 int height; /* picture height in pixels */

47 int width; /* picture width in pixels */

48 AVRational sar[2]; /* sample aspect ratios for 4:3 and 16:9 */

49 enum AVPixelFormat pix_fmt; /* picture pixel format */

50 int bpm; /* blocks per macroblock */

51 const uint8_t *block_sizes; /* AC block sizes, in bits */

52 int audio_stride; /* size of audio_shuffle table */

53 int audio_min_samples[3]; /* min amount of audio samples */

54 /* for 48kHz, 44.1kHz and 32kHz */

55 int audio_samples_dist[5]; /* how many samples are supposed to be */

56 /* in each frame in a 5 frames window */

57 const uint8_t (*audio_shuffle)[9]; /* PCM shuffling table */

58 } AVDVProfile;

59

60 /**

61 * Get a DV profile for the provided compressed frame.

62 *

63 * @param sys the profile used for the previous frame, may be NULL

64 * @param frame the compressed data buffer

65 * @param buf_size size of the buffer in bytes

66 * @return the DV profile for the supplied data or NULL on failure

67 */

68 const AVDVProfile *av_dv_frame_profile(const AVDVProfile *sys,

69 const uint8_t *frame, unsigned buf_size);

70

71 /**

72 * Get a DV profile for the provided stream parameters.

73 */

74 const AVDVProfile *av_dv_codec_profile(int width, int height, enum AVPixelFormat pix_fmt);

75

76 /**

77 * Get a DV profile for the provided stream parameters.

78 * The frame rate is used as a best-effort parameter.

79 */

80 const AVDVProfile *av_dv_codec_profile2(int width, int height, enum AVPixelFormat pix_fmt, AVRational frame_rate);

81

82 #endif /* AVCODEC_DV_PROFILE_H */

AVPixelFormat

Pixel format.

Definition: pixfmt.h:71

AVDVProfile::sar

AVRational sar[2]

Definition: dv_profile.h:48

av_dv_codec_profile

const AVDVProfile * av_dv_codec_profile(int width, int height, enum AVPixelFormat pix_fmt)

Get a DV profile for the provided stream parameters.

Definition: dv_profile.c:305

AVDVProfile::difseg_size

int difseg_size

Definition: dv_profile.h:42

AVDVProfile::dsf

int dsf

Definition: dv_profile.h:39

static enum AVPixelFormat pix_fmt

Definition: demux_decode.c:41

AVDVProfile::pix_fmt

enum AVPixelFormat pix_fmt

Definition: dv_profile.h:49

AVDVProfile::n_difchan

int n_difchan

Definition: dv_profile.h:43

Rational number (pair of numerator and denominator).

Definition: rational.h:58

av_dv_frame_profile

const AVDVProfile * av_dv_frame_profile(const AVDVProfile *sys, const uint8_t *frame, unsigned buf_size)

Get a DV profile for the provided compressed frame.

Definition: dv_profile.c:299

AVDVProfile::audio_stride

int audio_stride

Definition: dv_profile.h:52

#define height

Definition: dsp.h:89

AVDVProfile::height

int height

Definition: dv_profile.h:46

AVDVProfile::block_sizes

const uint8_t * block_sizes

Definition: dv_profile.h:51

AVDVProfile::audio_samples_dist

int audio_samples_dist[5]

Definition: dv_profile.h:55

AVDVProfile::ltc_divisor

int ltc_divisor

Definition: dv_profile.h:45

AVDVProfile::width

int width

Definition: dv_profile.h:47

these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame

Definition: filter_design.txt:265

AVDVProfile::video_stype

int video_stype

Definition: dv_profile.h:40

AVDVProfile::audio_min_samples

int audio_min_samples[3]

Definition: dv_profile.h:53

Definition: dv_profile.h:38

AVDVProfile::time_base

AVRational time_base

Definition: dv_profile.h:44

AVDVProfile::audio_shuffle

const uint8_t(* audio_shuffle)[9]

Definition: dv_profile.h:57

AVDVProfile::bpm

int bpm

Definition: dv_profile.h:50

#define width

Definition: dsp.h:89

av_dv_codec_profile2

const AVDVProfile * av_dv_codec_profile2(int width, int height, enum AVPixelFormat pix_fmt, AVRational frame_rate)

Get a DV profile for the provided stream parameters.

Definition: dv_profile.c:315

AVDVProfile::frame_size

int frame_size

Definition: dv_profile.h:41

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