FFmpeg
buffersrc.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,
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11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
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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 AVFILTER_BUFFERSRC_H
20 #define AVFILTER_BUFFERSRC_H
21 
22 /**
23  * @file
24  * @ingroup lavfi_buffersrc
25  * Memory buffer source API.
26  */
27 
28 #include "avfilter.h"
29 
30 /**
31  * @defgroup lavfi_buffersrc Buffer source API
32  * @ingroup lavfi
33  * @{
34  */
35 
36 enum {
37 
38  /**
39  * Do not check for format changes.
40  */
42 
43  /**
44  * Immediately push the frame to the output.
45  */
47 
48  /**
49  * Keep a reference to the frame.
50  * If the frame if reference-counted, create a new reference; otherwise
51  * copy the frame data.
52  */
54 
55 };
56 
57 /**
58  * Get the number of failed requests.
59  *
60  * A failed request is when the request_frame method is called while no
61  * frame is present in the buffer.
62  * The number is reset when a frame is added.
63  */
65 
66 /**
67  * This structure contains the parameters describing the frames that will be
68  * passed to this filter.
69  *
70  * It should be allocated with av_buffersrc_parameters_alloc() and freed with
71  * av_free(). All the allocated fields in it remain owned by the caller.
72  */
73 typedef struct AVBufferSrcParameters {
74  /**
75  * video: the pixel format, value corresponds to enum AVPixelFormat
76  * audio: the sample format, value corresponds to enum AVSampleFormat
77  */
78  int format;
79  /**
80  * The timebase to be used for the timestamps on the input frames.
81  */
83 
84  /**
85  * Video only, the display dimensions of the input frames.
86  */
87  int width, height;
88 
89  /**
90  * Video only, the sample (pixel) aspect ratio.
91  */
93 
94  /**
95  * Video only, the frame rate of the input video. This field must only be
96  * set to a non-zero value if input stream has a known constant framerate
97  * and should be left at its initial value if the framerate is variable or
98  * unknown.
99  */
101 
102  /**
103  * Video with a hwaccel pixel format only. This should be a reference to an
104  * AVHWFramesContext instance describing the input frames.
105  */
107 
108  /**
109  * Audio only, the audio sampling rate in samples per second.
110  */
112 
113 #if FF_API_OLD_CHANNEL_LAYOUT
114  /**
115  * Audio only, the audio channel layout
116  * @deprecated use ch_layout
117  */
119  uint64_t channel_layout;
120 #endif
121 
122  /**
123  * Audio only, the audio channel layout
124  */
126 
127  /**
128  * Video only, the YUV colorspace and range.
129  */
133 
134 /**
135  * Allocate a new AVBufferSrcParameters instance. It should be freed by the
136  * caller with av_free().
137  */
139 
140 /**
141  * Initialize the buffersrc or abuffersrc filter with the provided parameters.
142  * This function may be called multiple times, the later calls override the
143  * previous ones. Some of the parameters may also be set through AVOptions, then
144  * whatever method is used last takes precedence.
145  *
146  * @param ctx an instance of the buffersrc or abuffersrc filter
147  * @param param the stream parameters. The frames later passed to this filter
148  * must conform to those parameters. All the allocated fields in
149  * param remain owned by the caller, libavfilter will make internal
150  * copies or references when necessary.
151  * @return 0 on success, a negative AVERROR code on failure.
152  */
154 
155 /**
156  * Add a frame to the buffer source.
157  *
158  * @param ctx an instance of the buffersrc filter
159  * @param frame frame to be added. If the frame is reference counted, this
160  * function will make a new reference to it. Otherwise the frame data will be
161  * copied.
162  *
163  * @return 0 on success, a negative AVERROR on error
164  *
165  * This function is equivalent to av_buffersrc_add_frame_flags() with the
166  * AV_BUFFERSRC_FLAG_KEEP_REF flag.
167  */
170 
171 /**
172  * Add a frame to the buffer source.
173  *
174  * @param ctx an instance of the buffersrc filter
175  * @param frame frame to be added. If the frame is reference counted, this
176  * function will take ownership of the reference(s) and reset the frame.
177  * Otherwise the frame data will be copied. If this function returns an error,
178  * the input frame is not touched.
179  *
180  * @return 0 on success, a negative AVERROR on error.
181  *
182  * @note the difference between this function and av_buffersrc_write_frame() is
183  * that av_buffersrc_write_frame() creates a new reference to the input frame,
184  * while this function takes ownership of the reference passed to it.
185  *
186  * This function is equivalent to av_buffersrc_add_frame_flags() without the
187  * AV_BUFFERSRC_FLAG_KEEP_REF flag.
188  */
191 
192 /**
193  * Add a frame to the buffer source.
194  *
195  * By default, if the frame is reference-counted, this function will take
196  * ownership of the reference(s) and reset the frame. This can be controlled
197  * using the flags.
198  *
199  * If this function returns an error, the input frame is not touched.
200  *
201  * @param buffer_src pointer to a buffer source context
202  * @param frame a frame, or NULL to mark EOF
203  * @param flags a combination of AV_BUFFERSRC_FLAG_*
204  * @return >= 0 in case of success, a negative AVERROR code
205  * in case of failure
206  */
209  AVFrame *frame, int flags);
210 
211 /**
212  * Close the buffer source after EOF.
213  *
214  * This is similar to passing NULL to av_buffersrc_add_frame_flags()
215  * except it takes the timestamp of the EOF, i.e. the timestamp of the end
216  * of the last frame.
217  */
218 int av_buffersrc_close(AVFilterContext *ctx, int64_t pts, unsigned flags);
219 
220 /**
221  * @}
222  */
223 
224 #endif /* AVFILTER_BUFFERSRC_H */
AVBufferSrcParameters::color_space
enum AVColorSpace color_space
Video only, the YUV colorspace and range.
Definition: buffersrc.h:130
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
av_buffersrc_add_frame
av_warn_unused_result int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame)
Add a frame to the buffer source.
Definition: buffersrc.c:184
AVBufferSrcParameters::height
int height
Definition: buffersrc.h:87
AVBufferSrcParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only, the sample (pixel) aspect ratio.
Definition: buffersrc.h:92
pts
static int64_t pts
Definition: transcode_aac.c:643
AVBufferSrcParameters::ch_layout
AVChannelLayout ch_layout
Audio only, the audio channel layout.
Definition: buffersrc.h:125
AV_BUFFERSRC_FLAG_KEEP_REF
@ AV_BUFFERSRC_FLAG_KEEP_REF
Keep a reference to the frame.
Definition: buffersrc.h:53
AV_BUFFERSRC_FLAG_PUSH
@ AV_BUFFERSRC_FLAG_PUSH
Immediately push the frame to the output.
Definition: buffersrc.h:46
ctx
AVFormatContext * ctx
Definition: movenc.c:48
frame
static AVFrame * frame
Definition: demux_decode.c:54
AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT
@ AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT
Do not check for format changes.
Definition: buffersrc.h:41
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVBufferSrcParameters::frame_rate
AVRational frame_rate
Video only, the frame rate of the input video.
Definition: buffersrc.h:100
av_buffersrc_close
int av_buffersrc_close(AVFilterContext *ctx, int64_t pts, unsigned flags)
Close the buffer source after EOF.
Definition: buffersrc.c:312
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:313
av_buffersrc_parameters_alloc
AVBufferSrcParameters * av_buffersrc_parameters_alloc(void)
Allocate a new AVBufferSrcParameters instance.
Definition: buffersrc.c:105
AVBufferSrcParameters::hw_frames_ctx
AVBufferRef * hw_frames_ctx
Video with a hwaccel pixel format only.
Definition: buffersrc.h:106
AVBufferSrcParameters::sample_rate
int sample_rate
Audio only, the audio sampling rate in samples per second.
Definition: buffersrc.h:111
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
AVBufferSrcParameters::time_base
AVRational time_base
The timebase to be used for the timestamps on the input frames.
Definition: buffersrc.h:82
av_warn_unused_result
#define av_warn_unused_result
Definition: attributes.h:64
av_buffersrc_parameters_set
int av_buffersrc_parameters_set(AVFilterContext *ctx, AVBufferSrcParameters *param)
Initialize the buffersrc or abuffersrc filter with the provided parameters.
Definition: buffersrc.c:118
AVBufferSrcParameters::width
int width
Video only, the display dimensions of the input frames.
Definition: buffersrc.h:87
av_buffersrc_add_frame_flags
av_warn_unused_result int av_buffersrc_add_frame_flags(AVFilterContext *buffer_src, AVFrame *frame, int flags)
Add a frame to the buffer source.
Definition: buffersrc.c:203
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:613
AVBufferSrcParameters::color_range
enum AVColorRange color_range
Definition: buffersrc.h:131
AVBufferSrcParameters
This structure contains the parameters describing the frames that will be passed to this filter.
Definition: buffersrc.h:73
AVBufferSrcParameters::format
int format
video: the pixel format, value corresponds to enum AVPixelFormat audio: the sample format,...
Definition: buffersrc.h:78
avfilter.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:409
av_buffersrc_get_nb_failed_requests
unsigned av_buffersrc_get_nb_failed_requests(AVFilterContext *buffer_src)
Get the number of failed requests.
Definition: buffersrc.c:347
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
av_buffersrc_write_frame
av_warn_unused_result int av_buffersrc_write_frame(AVFilterContext *ctx, const AVFrame *frame)
Add a frame to the buffer source.
Definition: buffersrc.c:178
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:652