FFmpeg  4.0
dv_profile.h
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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 #include "avcodec.h"
27 
28 /* minimum number of bytes to read from a DV stream in order to
29  * determine the profile */
30 #define DV_PROFILE_BYTES (6 * 80) /* 6 DIF blocks */
31 
32 
33 /*
34  * AVDVProfile is used to express the differences between various
35  * DV flavors. For now it's primarily used for differentiating
36  * 525/60 and 625/50, but the plans are to use it for various
37  * DV specs as well (e.g. SMPTE314M vs. IEC 61834).
38  */
39 typedef struct AVDVProfile {
40  int dsf; /* value of the dsf in the DV header */
41  int video_stype; /* stype for VAUX source pack */
42  int frame_size; /* total size of one frame in bytes */
43  int difseg_size; /* number of DIF segments per DIF channel */
44  int n_difchan; /* number of DIF channels per frame */
45  AVRational time_base; /* 1/framerate */
46  int ltc_divisor; /* FPS from the LTS standpoint */
47  int height; /* picture height in pixels */
48  int width; /* picture width in pixels */
49  AVRational sar[2]; /* sample aspect ratios for 4:3 and 16:9 */
50  enum AVPixelFormat pix_fmt; /* picture pixel format */
51  int bpm; /* blocks per macroblock */
52  const uint8_t *block_sizes; /* AC block sizes, in bits */
53  int audio_stride; /* size of audio_shuffle table */
54  int audio_min_samples[3]; /* min amount of audio samples */
55  /* for 48kHz, 44.1kHz and 32kHz */
56  int audio_samples_dist[5]; /* how many samples are supposed to be */
57  /* in each frame in a 5 frames window */
58  const uint8_t (*audio_shuffle)[9]; /* PCM shuffling table */
59 } AVDVProfile;
60 
61 /**
62  * Get a DV profile for the provided compressed frame.
63  *
64  * @param sys the profile used for the previous frame, may be NULL
65  * @param frame the compressed data buffer
66  * @param buf_size size of the buffer in bytes
67  * @return the DV profile for the supplied data or NULL on failure
68  */
70  const uint8_t *frame, unsigned buf_size);
71 
72 /**
73  * Get a DV profile for the provided stream parameters.
74  */
76 
77 /**
78  * Get a DV profile for the provided stream parameters.
79  * The frame rate is used as a best-effort parameter.
80  */
82 
83 #endif /* AVCODEC_DV_PROFILE_H */
const uint8_t * block_sizes
Definition: dv_profile.h:52
int ltc_divisor
Definition: dv_profile.h:46
int audio_samples_dist[5]
Definition: dv_profile.h:56
uint8_t
static AVFrame * frame
int difseg_size
Definition: dv_profile.h:43
enum AVPixelFormat pix_fmt
Definition: dv_profile.h:50
AVRational time_base
Definition: dv_profile.h:45
const uint8_t(* audio_shuffle)[9]
Definition: dv_profile.h:58
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:300
int audio_min_samples[3]
Definition: dv_profile.h:54
int frame_size
Definition: dv_profile.h:42
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:306
Libavcodec external API header.
int audio_stride
Definition: dv_profile.h:53
AVRational sar[2]
Definition: dv_profile.h:49
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int video_stype
Definition: dv_profile.h:41
Utilties for rational number calculation.
pixel format definitions
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:316
int n_difchan
Definition: dv_profile.h:44
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60