FFmpeg
vf_framepack.c
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1 /*
2  * Copyright (c) 2013 Vittorio Giovara
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * Generate a frame packed video, by combining two views in a single surface.
24  */
25 
26 #include <string.h>
27 
28 #include "libavutil/common.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/pixdesc.h"
32 #include "libavutil/rational.h"
33 #include "libavutil/stereo3d.h"
34 
35 #include "avfilter.h"
36 #include "formats.h"
37 #include "internal.h"
38 #include "video.h"
39 
40 #define LEFT 0
41 #define RIGHT 1
42 
43 typedef struct FramepackContext {
44  const AVClass *class;
45 
46  const AVPixFmtDescriptor *pix_desc; ///< agreed pixel format
47 
48  enum AVStereo3DType format; ///< frame pack type output
49 
50  AVFrame *input_views[2]; ///< input frames
51 
52  int64_t double_pts; ///< new pts for frameseq mode
54 
55 static const enum AVPixelFormat formats_supported[] = {
60 };
61 
63 {
64  // this will ensure that formats are the same on all pads
66  if (!fmts_list)
67  return AVERROR(ENOMEM);
68  return ff_set_common_formats(ctx, fmts_list);
69 }
70 
72 {
73  FramepackContext *s = ctx->priv;
74 
75  // clean any leftover frame
78 }
79 
80 static int config_output(AVFilterLink *outlink)
81 {
82  AVFilterContext *ctx = outlink->src;
83  FramepackContext *s = outlink->src->priv;
84 
85  int width = ctx->inputs[LEFT]->w;
86  int height = ctx->inputs[LEFT]->h;
87  AVRational time_base = ctx->inputs[LEFT]->time_base;
88  AVRational frame_rate = ctx->inputs[LEFT]->frame_rate;
89 
90  // check size and fps match on the other input
91  if (width != ctx->inputs[RIGHT]->w ||
92  height != ctx->inputs[RIGHT]->h) {
93  av_log(ctx, AV_LOG_ERROR,
94  "Left and right sizes differ (%dx%d vs %dx%d).\n",
95  width, height,
96  ctx->inputs[RIGHT]->w, ctx->inputs[RIGHT]->h);
97  return AVERROR_INVALIDDATA;
98  } else if (av_cmp_q(time_base, ctx->inputs[RIGHT]->time_base) != 0) {
99  av_log(ctx, AV_LOG_ERROR,
100  "Left and right time bases differ (%d/%d vs %d/%d).\n",
101  time_base.num, time_base.den,
102  ctx->inputs[RIGHT]->time_base.num,
103  ctx->inputs[RIGHT]->time_base.den);
104  return AVERROR_INVALIDDATA;
105  } else if (av_cmp_q(frame_rate, ctx->inputs[RIGHT]->frame_rate) != 0) {
106  av_log(ctx, AV_LOG_ERROR,
107  "Left and right framerates differ (%d/%d vs %d/%d).\n",
108  frame_rate.num, frame_rate.den,
109  ctx->inputs[RIGHT]->frame_rate.num,
110  ctx->inputs[RIGHT]->frame_rate.den);
111  return AVERROR_INVALIDDATA;
112  }
113 
114  s->pix_desc = av_pix_fmt_desc_get(outlink->format);
115  if (!s->pix_desc)
116  return AVERROR_BUG;
117 
118  // modify output properties as needed
119  switch (s->format) {
121  time_base.den *= 2;
122  frame_rate.num *= 2;
123 
125  break;
126  case AV_STEREO3D_COLUMNS:
128  width *= 2;
129  break;
130  case AV_STEREO3D_LINES:
132  height *= 2;
133  break;
134  default:
135  av_log(ctx, AV_LOG_ERROR, "Unknown packing mode.");
136  return AVERROR_INVALIDDATA;
137  }
138 
139  outlink->w = width;
140  outlink->h = height;
141  outlink->time_base = time_base;
142  outlink->frame_rate = frame_rate;
143 
144  return 0;
145 }
146 
147 static void horizontal_frame_pack(AVFilterLink *outlink,
148  AVFrame *out,
149  int interleaved)
150 {
151  AVFilterContext *ctx = outlink->src;
152  FramepackContext *s = ctx->priv;
153  int i, plane;
154 
155  if (interleaved) {
156  const uint8_t *leftp = s->input_views[LEFT]->data[0];
157  const uint8_t *rightp = s->input_views[RIGHT]->data[0];
158  uint8_t *dstp = out->data[0];
159  int length = out->width / 2;
160  int lines = out->height;
161 
162  for (plane = 0; plane < s->pix_desc->nb_components; plane++) {
163  if (plane == 1 || plane == 2) {
164  length = AV_CEIL_RSHIFT(out->width / 2, s->pix_desc->log2_chroma_w);
165  lines = AV_CEIL_RSHIFT(out->height, s->pix_desc->log2_chroma_h);
166  }
167  for (i = 0; i < lines; i++) {
168  int j;
169  leftp = s->input_views[LEFT]->data[plane] +
170  s->input_views[LEFT]->linesize[plane] * i;
171  rightp = s->input_views[RIGHT]->data[plane] +
172  s->input_views[RIGHT]->linesize[plane] * i;
173  dstp = out->data[plane] + out->linesize[plane] * i;
174  for (j = 0; j < length; j++) {
175  // interpolate chroma as necessary
176  if ((s->pix_desc->log2_chroma_w ||
177  s->pix_desc->log2_chroma_h) &&
178  (plane == 1 || plane == 2)) {
179  *dstp++ = (*leftp + *rightp) / 2;
180  *dstp++ = (*leftp + *rightp) / 2;
181  } else {
182  *dstp++ = *leftp;
183  *dstp++ = *rightp;
184  }
185  leftp += 1;
186  rightp += 1;
187  }
188  }
189  }
190  } else {
191  for (i = 0; i < 2; i++) {
192  const uint8_t *src[4];
193  uint8_t *dst[4];
194  int sub_w = s->input_views[i]->width >> s->pix_desc->log2_chroma_w;
195 
196  src[0] = s->input_views[i]->data[0];
197  src[1] = s->input_views[i]->data[1];
198  src[2] = s->input_views[i]->data[2];
199 
200  dst[0] = out->data[0] + i * s->input_views[i]->width;
201  dst[1] = out->data[1] + i * sub_w;
202  dst[2] = out->data[2] + i * sub_w;
203 
204  av_image_copy(dst, out->linesize, src, s->input_views[i]->linesize,
205  s->input_views[i]->format,
206  s->input_views[i]->width,
207  s->input_views[i]->height);
208  }
209  }
210 }
211 
212 static void vertical_frame_pack(AVFilterLink *outlink,
213  AVFrame *out,
214  int interleaved)
215 {
216  AVFilterContext *ctx = outlink->src;
217  FramepackContext *s = ctx->priv;
218  int i;
219 
220  for (i = 0; i < 2; i++) {
221  const uint8_t *src[4];
222  uint8_t *dst[4];
223  int linesizes[4];
224  int sub_h = s->input_views[i]->height >> s->pix_desc->log2_chroma_h;
225 
226  src[0] = s->input_views[i]->data[0];
227  src[1] = s->input_views[i]->data[1];
228  src[2] = s->input_views[i]->data[2];
229 
230  dst[0] = out->data[0] + i * out->linesize[0] *
231  (interleaved + s->input_views[i]->height * (1 - interleaved));
232  dst[1] = out->data[1] + i * out->linesize[1] *
233  (interleaved + sub_h * (1 - interleaved));
234  dst[2] = out->data[2] + i * out->linesize[2] *
235  (interleaved + sub_h * (1 - interleaved));
236 
237  linesizes[0] = out->linesize[0] +
238  interleaved * out->linesize[0];
239  linesizes[1] = out->linesize[1] +
240  interleaved * out->linesize[1];
241  linesizes[2] = out->linesize[2] +
242  interleaved * out->linesize[2];
243 
244  av_image_copy(dst, linesizes, src, s->input_views[i]->linesize,
245  s->input_views[i]->format,
246  s->input_views[i]->width,
247  s->input_views[i]->height);
248  }
249 }
250 
252  AVFrame *dst)
253 {
254  AVFilterContext *ctx = outlink->src;
255  FramepackContext *s = ctx->priv;
256  switch (s->format) {
258  horizontal_frame_pack(outlink, dst, 0);
259  break;
260  case AV_STEREO3D_COLUMNS:
261  horizontal_frame_pack(outlink, dst, 1);
262  break;
264  vertical_frame_pack(outlink, dst, 0);
265  break;
266  case AV_STEREO3D_LINES:
267  vertical_frame_pack(outlink, dst, 1);
268  break;
269  }
270 }
271 
272 static int try_push_frame(AVFilterContext *ctx);
273 
275 {
276  FramepackContext *s = inlink->dst->priv;
277  s->input_views[LEFT] = frame;
278  return try_push_frame(inlink->dst);
279 }
280 
282 {
283  FramepackContext *s = inlink->dst->priv;
284  s->input_views[RIGHT] = frame;
285  return try_push_frame(inlink->dst);
286 }
287 
288 static int request_frame(AVFilterLink *outlink)
289 {
290  AVFilterContext *ctx = outlink->src;
291  FramepackContext *s = ctx->priv;
292  int ret, i;
293 
294  /* get a frame on the either input, stop as soon as a video ends */
295  for (i = 0; i < 2; i++) {
296  if (!s->input_views[i]) {
297  ret = ff_request_frame(ctx->inputs[i]);
298  if (ret < 0)
299  return ret;
300  }
301  }
302  return 0;
303 }
304 
306 {
307  FramepackContext *s = ctx->priv;
308  AVFilterLink *outlink = ctx->outputs[0];
309  AVStereo3D *stereo;
310  int ret, i;
311 
312  if (!(s->input_views[0] && s->input_views[1]))
313  return 0;
314  if (s->format == AV_STEREO3D_FRAMESEQUENCE) {
315  if (s->double_pts == AV_NOPTS_VALUE)
316  s->double_pts = s->input_views[LEFT]->pts;
317 
318  for (i = 0; i < 2; i++) {
319  // set correct timestamps
320  s->input_views[i]->pts = s->double_pts++;
321 
322  // set stereo3d side data
324  if (!stereo)
325  return AVERROR(ENOMEM);
326  stereo->type = s->format;
327  stereo->view = i == LEFT ? AV_STEREO3D_VIEW_LEFT
329 
330  // filter the frame and immediately relinquish its pointer
331  ret = ff_filter_frame(outlink, s->input_views[i]);
332  s->input_views[i] = NULL;
333  if (ret < 0)
334  return ret;
335  }
336  return ret;
337  } else {
338  AVFrame *dst = ff_get_video_buffer(outlink, outlink->w, outlink->h);
339  if (!dst)
340  return AVERROR(ENOMEM);
341 
342  spatial_frame_pack(outlink, dst);
343 
344  // get any property from the original frame
345  ret = av_frame_copy_props(dst, s->input_views[LEFT]);
346  if (ret < 0) {
347  av_frame_free(&dst);
348  return ret;
349  }
350 
351  for (i = 0; i < 2; i++)
352  av_frame_free(&s->input_views[i]);
353 
354  // set stereo3d side data
355  stereo = av_stereo3d_create_side_data(dst);
356  if (!stereo) {
357  av_frame_free(&dst);
358  return AVERROR(ENOMEM);
359  }
360  stereo->type = s->format;
361 
362  return ff_filter_frame(outlink, dst);
363  }
364 }
365 
366 #define OFFSET(x) offsetof(FramepackContext, x)
367 #define V AV_OPT_FLAG_VIDEO_PARAM
368 static const AVOption framepack_options[] = {
369  { "format", "Frame pack output format", OFFSET(format), AV_OPT_TYPE_INT,
370  { .i64 = AV_STEREO3D_SIDEBYSIDE }, 0, INT_MAX, .flags = V, .unit = "format" },
371  { "sbs", "Views are packed next to each other", 0, AV_OPT_TYPE_CONST,
372  { .i64 = AV_STEREO3D_SIDEBYSIDE }, INT_MIN, INT_MAX, .flags = V, .unit = "format" },
373  { "tab", "Views are packed on top of each other", 0, AV_OPT_TYPE_CONST,
374  { .i64 = AV_STEREO3D_TOPBOTTOM }, INT_MIN, INT_MAX, .flags = V, .unit = "format" },
375  { "frameseq", "Views are one after the other", 0, AV_OPT_TYPE_CONST,
376  { .i64 = AV_STEREO3D_FRAMESEQUENCE }, INT_MIN, INT_MAX, .flags = V, .unit = "format" },
377  { "lines", "Views are interleaved by lines", 0, AV_OPT_TYPE_CONST,
378  { .i64 = AV_STEREO3D_LINES }, INT_MIN, INT_MAX, .flags = V, .unit = "format" },
379  { "columns", "Views are interleaved by columns", 0, AV_OPT_TYPE_CONST,
380  { .i64 = AV_STEREO3D_COLUMNS }, INT_MIN, INT_MAX, .flags = V, .unit = "format" },
381  { NULL },
382 };
383 
384 AVFILTER_DEFINE_CLASS(framepack);
385 
386 static const AVFilterPad framepack_inputs[] = {
387  {
388  .name = "left",
389  .type = AVMEDIA_TYPE_VIDEO,
390  .filter_frame = filter_frame_left,
391  .needs_fifo = 1,
392  },
393  {
394  .name = "right",
395  .type = AVMEDIA_TYPE_VIDEO,
396  .filter_frame = filter_frame_right,
397  .needs_fifo = 1,
398  },
399  { NULL }
400 };
401 
402 static const AVFilterPad framepack_outputs[] = {
403  {
404  .name = "packed",
405  .type = AVMEDIA_TYPE_VIDEO,
406  .config_props = config_output,
407  .request_frame = request_frame,
408  },
409  { NULL }
410 };
411 
413  .name = "framepack",
414  .description = NULL_IF_CONFIG_SMALL("Generate a frame packed stereoscopic video."),
415  .priv_size = sizeof(FramepackContext),
416  .priv_class = &framepack_class,
418  .inputs = framepack_inputs,
419  .outputs = framepack_outputs,
421 };
int plane
Definition: avisynth_c.h:384
#define NULL
Definition: coverity.c:32
static int filter_frame_right(AVFilterLink *inlink, AVFrame *frame)
Definition: vf_framepack.c:281
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2522
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
enum AVStereo3DView view
Determines which views are packed.
Definition: stereo3d.h:190
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:71
misc image utilities
Main libavfilter public API header.
static int try_push_frame(AVFilterContext *ctx)
Definition: vf_framepack.c:305
int num
Numerator.
Definition: rational.h:59
Frame contains only the right view.
Definition: stereo3d.h:161
static enum AVPixelFormat formats_supported[]
Definition: vf_framepack.c:55
Views are next to each other.
Definition: stereo3d.h:67
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:99
#define src
Definition: vp8dsp.c:254
static void vertical_frame_pack(AVFilterLink *outlink, AVFrame *out, int interleaved)
Definition: vf_framepack.c:212
#define RIGHT
Definition: vf_framepack.c:41
uint8_t log2_chroma_w
Amount to shift the luma width right to find the chroma width.
Definition: pixdesc.h:92
Frame contains only the left view.
Definition: stereo3d.h:156
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
const char * name
Pad name.
Definition: internal.h:60
#define OFFSET(x)
Definition: vf_framepack.c:366
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
uint8_t
#define av_cold
Definition: attributes.h:82
AVFILTER_DEFINE_CLASS(framepack)
static av_cold int uninit(AVCodecContext *avctx)
Definition: crystalhd.c:279
AVOptions.
Stereo 3D type: this structure describes how two videos are packed within a single video surface...
Definition: stereo3d.h:176
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:388
static int query_formats(AVFilterContext *ctx)
Definition: vf_framepack.c:62
#define height
planar YUV 4:4:0 full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV440P and setting color_range...
Definition: pixfmt.h:100
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting col...
Definition: pixfmt.h:79
static void horizontal_frame_pack(AVFilterLink *outlink, AVFrame *out, int interleaved)
Definition: vf_framepack.c:147
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
int width
Definition: frame.h:353
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:568
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:101
#define V
Definition: vf_framepack.c:367
AVFilter ff_vf_framepack
Definition: vf_framepack.c:412
BYTE * dstp
Definition: avisynth_c.h:908
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
Views are packed per line, as if interlaced.
Definition: stereo3d.h:129
void * priv
private data for use by the filter
Definition: avfilter.h:353
int64_t double_pts
new pts for frameseq mode
Definition: vf_framepack.c:52
GLsizei GLsizei * length
Definition: opengl_enc.c:114
static int filter_frame_left(AVFilterLink *inlink, AVFrame *frame)
Definition: vf_framepack.c:274
void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4], const uint8_t *src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Copy image in src_data to dst_data.
Definition: imgutils.c:387
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:70
AVStereo3D * av_stereo3d_create_side_data(AVFrame *frame)
Allocate a complete AVFrameSideData and add it to the frame.
Definition: stereo3d.c:33
Views are alternated temporally.
Definition: stereo3d.h:92
uint8_t nb_components
The number of components each pixel has, (1-4)
Definition: pixdesc.h:83
AVStereo3DType
List of possible 3D Types.
Definition: stereo3d.h:51
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:78
#define width
AVFrame * input_views[2]
input frames
Definition: vf_framepack.c:50
AVFormatContext * ctx
Definition: movenc.c:48
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
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:368
enum AVStereo3DType type
How views are packed within the video.
Definition: stereo3d.h:180
Views are on top of each other.
Definition: stereo3d.h:79
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
#define LEFT
Definition: vf_framepack.c:40
enum AVStereo3DType format
frame pack type output
Definition: vf_framepack.c:48
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 inputs
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:50
planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
Definition: pixfmt.h:72
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static int request_frame(AVFilterLink *outlink)
Definition: vf_framepack.c:288
static const AVFilterPad framepack_inputs[]
Definition: vf_framepack.c:386
const char * name
Filter name.
Definition: avfilter.h:148
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
const AVPixFmtDescriptor * pix_desc
agreed pixel format
Definition: vf_framepack.c:46
static int config_output(AVFilterLink *outlink)
Definition: vf_framepack.c:80
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
static av_cold void framepack_uninit(AVFilterContext *ctx)
Definition: vf_framepack.c:71
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
static int av_cmp_q(AVRational a, AVRational b)
Compare two rationals.
Definition: rational.h:89
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
common internal and external API header
Utilties for rational number calculation.
planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting col...
Definition: pixfmt.h:80
Stereoscopic video.
Views are packed per column.
Definition: stereo3d.h:141
int den
Denominator.
Definition: rational.h:60
static const AVOption framepack_options[]
Definition: vf_framepack.c:368
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
int height
Definition: frame.h:353
FILE * out
Definition: movenc.c:54
static const AVFilterPad framepack_outputs[]
Definition: vf_framepack.c:402
#define av_always_inline
Definition: attributes.h:39
static av_always_inline void spatial_frame_pack(AVFilterLink *outlink, AVFrame *dst)
Definition: vf_framepack.c:251
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:407
internal API functions
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:654
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
#define AV_CEIL_RSHIFT(a, b)
Definition: common.h:58