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 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 */ 41 AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT = 1, 42 43 /** 44 * Immediately push the frame to the output. 45 */ 46 AV_BUFFERSRC_FLAG_PUSH = 4, 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 */ 53 AV_BUFFERSRC_FLAG_KEEP_REF = 8, 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 */ 64 unsigned av_buffersrc_get_nb_failed_requests(AVFilterContext *buffer_src); 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 */ 82 AVRational time_base; 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 */ 92 AVRational sample_aspect_ratio; 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 */ 100 AVRational frame_rate; 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 */ 106 AVBufferRef *hw_frames_ctx; 107 108 /** 109 * Audio only, the audio sampling rate in samples per second. 110 */ 111 int sample_rate; 112 113 #if FF_API_OLD_CHANNEL_LAYOUT 114 /** 115 * Audio only, the audio channel layout 116 * @deprecated use ch_layout 117 */ 118 attribute_deprecated 119 uint64_t channel_layout; 120 #endif 121 122 /** 123 * Audio only, the audio channel layout 124 */ 125 AVChannelLayout ch_layout; 126 } AVBufferSrcParameters; 127 128 /** 129 * Allocate a new AVBufferSrcParameters instance. It should be freed by the 130 * caller with av_free(). 131 */ 132 AVBufferSrcParameters *av_buffersrc_parameters_alloc(void); 133 134 /** 135 * Initialize the buffersrc or abuffersrc filter with the provided parameters. 136 * This function may be called multiple times, the later calls override the 137 * previous ones. Some of the parameters may also be set through AVOptions, then 138 * whatever method is used last takes precedence. 139 * 140 * @param ctx an instance of the buffersrc or abuffersrc filter 141 * @param param the stream parameters. The frames later passed to this filter 142 * must conform to those parameters. All the allocated fields in 143 * param remain owned by the caller, libavfilter will make internal 144 * copies or references when necessary. 145 * @return 0 on success, a negative AVERROR code on failure. 146 */ 147 int av_buffersrc_parameters_set(AVFilterContext *ctx, AVBufferSrcParameters *param); 148 149 /** 150 * Add a frame to the buffer source. 151 * 152 * @param ctx an instance of the buffersrc filter 153 * @param frame frame to be added. If the frame is reference counted, this 154 * function will make a new reference to it. Otherwise the frame data will be 155 * copied. 156 * 157 * @return 0 on success, a negative AVERROR on error 158 * 159 * This function is equivalent to av_buffersrc_add_frame_flags() with the 160 * AV_BUFFERSRC_FLAG_KEEP_REF flag. 161 */ 162 av_warn_unused_result 163 int av_buffersrc_write_frame(AVFilterContext *ctx, const AVFrame *frame); 164 165 /** 166 * Add a frame to the buffer source. 167 * 168 * @param ctx an instance of the buffersrc filter 169 * @param frame frame to be added. If the frame is reference counted, this 170 * function will take ownership of the reference(s) and reset the frame. 171 * Otherwise the frame data will be copied. If this function returns an error, 172 * the input frame is not touched. 173 * 174 * @return 0 on success, a negative AVERROR on error. 175 * 176 * @note the difference between this function and av_buffersrc_write_frame() is 177 * that av_buffersrc_write_frame() creates a new reference to the input frame, 178 * while this function takes ownership of the reference passed to it. 179 * 180 * This function is equivalent to av_buffersrc_add_frame_flags() without the 181 * AV_BUFFERSRC_FLAG_KEEP_REF flag. 182 */ 183 av_warn_unused_result 184 int av_buffersrc_add_frame(AVFilterContext *ctx, AVFrame *frame); 185 186 /** 187 * Add a frame to the buffer source. 188 * 189 * By default, if the frame is reference-counted, this function will take 190 * ownership of the reference(s) and reset the frame. This can be controlled 191 * using the flags. 192 * 193 * If this function returns an error, the input frame is not touched. 194 * 195 * @param buffer_src pointer to a buffer source context 196 * @param frame a frame, or NULL to mark EOF 197 * @param flags a combination of AV_BUFFERSRC_FLAG_* 198 * @return >= 0 in case of success, a negative AVERROR code 199 * in case of failure 200 */ 201 av_warn_unused_result 202 int av_buffersrc_add_frame_flags(AVFilterContext *buffer_src, 203 AVFrame *frame, int flags); 204 205 /** 206 * Close the buffer source after EOF. 207 * 208 * This is similar to passing NULL to av_buffersrc_add_frame_flags() 209 * except it takes the timestamp of the EOF, i.e. the timestamp of the end 210 * of the last frame. 211 */ 212 int av_buffersrc_close(AVFilterContext *ctx, int64_t pts, unsigned flags); 213 214 /** 215 * @} 216 */ 217 218 #endif /* AVFILTER_BUFFERSRC_H */ 219