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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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19 #ifndef AVFILTER_BUFFERSRC_H
20 #define AVFILTER_BUFFERSRC_H
24 * @ingroup lavfi_buffersrc
25 * Memory buffer source API.
28 #include "libavcodec/avcodec.h"
32 * @defgroup lavfi_buffersrc Buffer source API
40 * Do not check for format changes.
42 AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT = 1,
45 * Immediately push the frame to the output.
47 AV_BUFFERSRC_FLAG_PUSH = 4,
50 * Keep a reference to the frame.
51 * If the frame if reference-counted, create a new reference; otherwise
52 * copy the frame data.
54 AV_BUFFERSRC_FLAG_KEEP_REF = 8,
59 * Get the number of failed requests.
61 * A failed request is when the request_frame method is called while no
62 * frame is present in the buffer.
63 * The number is reset when a frame is added.
65 unsigned av_buffersrc_get_nb_failed_requests(AVFilterContext *buffer_src);
68 * This structure contains the parameters describing the frames that will be
69 * passed to this filter.
71 * It should be allocated with av_buffersrc_parameters_alloc() and freed with
72 * av_free(). All the allocated fields in it remain owned by the caller.
74 typedef struct AVBufferSrcParameters {
76 * video: the pixel format, value corresponds to enum AVPixelFormat
77 * audio: the sample format, value corresponds to enum AVSampleFormat
81 * The timebase to be used for the timestamps on the input frames.
86 * Video only, the display dimensions of the input frames.
91 * Video only, the sample (pixel) aspect ratio.
93 AVRational sample_aspect_ratio;
96 * Video only, the frame rate of the input video. This field must only be
97 * set to a non-zero value if input stream has a known constant framerate
98 * and should be left at its initial value if the framerate is variable or
101 AVRational frame_rate;
104 * Video with a hwaccel pixel format only. This should be a reference to an
105 * AVHWFramesContext instance describing the input frames.
107 AVBufferRef *hw_frames_ctx;
110 * Audio only, the audio sampling rate in samples per secon.
115 * Audio only, the audio channel layout
117 uint64_t channel_layout;
118 } AVBufferSrcParameters;
121 * Allocate a new AVBufferSrcParameters instance. It should be freed by the
122 * caller with av_free().
124 AVBufferSrcParameters *av_buffersrc_parameters_alloc(void);
127 * Initialize the buffersrc or abuffersrc filter with the provided parameters.
128 * This function may be called multiple times, the later calls override the
129 * previous ones. Some of the parameters may also be set through AVOptions, then
130 * whatever method is used last takes precedence.
132 * @param ctx an instance of the buffersrc or abuffersrc filter
133 * @param param the stream parameters. The frames later passed to this filter
134 * must conform to those parameters. All the allocated fields in
135 * param remain owned by the caller, libavfilter will make internal
136 * copies or references when necessary.
137 * @return 0 on success, a negative AVERROR code on failure.
139 int av_buffersrc_parameters_set(AVFilterContext *ctx, AVBufferSrcParameters *param);
142 * Add a frame to the buffer source.
144 * @param ctx an instance of the buffersrc filter
145 * @param frame frame to be added. If the frame is reference counted, this
146 * function will make a new reference to it. Otherwise the frame data will be
149 * @return 0 on success, a negative AVERROR on error
151 * This function is equivalent to av_buffersrc_add_frame_flags() with the
152 * AV_BUFFERSRC_FLAG_KEEP_REF flag.
154 av_warn_unused_result
155 int av_buffersrc_write_frame(AVFilterContext *ctx, const AVFrame *frame);
158 * Add a frame to the buffer source.
160 * @param ctx an instance of the buffersrc filter
161 * @param frame frame to be added. If the frame is reference counted, this
162 * function will take ownership of the reference(s) and reset the frame.
163 * Otherwise the frame data will be copied. If this function returns an error,
164 * the input frame is not touched.
166 * @return 0 on success, a negative AVERROR on error.
168 * @note the difference between this function and av_buffersrc_write_frame() is
169 * that av_buffersrc_write_frame() creates a new reference to the input frame,
170 * while this function takes ownership of the reference passed to it.
172 * This function is equivalent to av_buffersrc_add_frame_flags() without the
173 * AV_BUFFERSRC_FLAG_KEEP_REF flag.
175 av_warn_unused_result
176 int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame);
179 * Add a frame to the buffer source.
181 * By default, if the frame is reference-counted, this function will take
182 * ownership of the reference(s) and reset the frame. This can be controlled
185 * If this function returns an error, the input frame is not touched.
187 * @param buffer_src pointer to a buffer source context
188 * @param frame a frame, or NULL to mark EOF
189 * @param flags a combination of AV_BUFFERSRC_FLAG_*
190 * @return >= 0 in case of success, a negative AVERROR code
193 av_warn_unused_result
194 int av_buffersrc_add_frame_flags(AVFilterContext *buffer_src,
195 AVFrame *frame, int flags);
202 #endif /* AVFILTER_BUFFERSRC_H */