FFmpeg
v4l2_m2m_enc.c
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1 /*
2  * V4L2 mem2mem encoders
3  *
4  * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
5  * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include <linux/videodev2.h>
25 #include <sys/ioctl.h>
26 #include <search.h>
27 #include "libavcodec/avcodec.h"
28 #include "libavutil/pixdesc.h"
29 #include "libavutil/pixfmt.h"
30 #include "libavutil/opt.h"
31 #include "v4l2_context.h"
32 #include "v4l2_m2m.h"
33 
34 #define MPEG_CID(x) V4L2_CID_MPEG_VIDEO_##x
35 #define MPEG_VIDEO(x) V4L2_MPEG_VIDEO_##x
36 
37 static inline void v4l2_set_timeperframe(V4L2m2mContext *s, unsigned int num, unsigned int den)
38 {
39  struct v4l2_streamparm parm = { 0 };
40 
41  parm.type = V4L2_TYPE_IS_MULTIPLANAR(s->output.type) ? V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE : V4L2_BUF_TYPE_VIDEO_OUTPUT;
42  parm.parm.output.timeperframe.denominator = den;
43  parm.parm.output.timeperframe.numerator = num;
44 
45  if (ioctl(s->fd, VIDIOC_S_PARM, &parm) < 0)
46  av_log(s->avctx, AV_LOG_WARNING, "Failed to set timeperframe");
47 }
48 
49 static inline void v4l2_set_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int value, const char *name)
50 {
51  struct v4l2_ext_controls ctrls = { { 0 } };
52  struct v4l2_ext_control ctrl = { 0 };
53 
54  /* set ctrls */
55  ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
56  ctrls.controls = &ctrl;
57  ctrls.count = 1;
58 
59  /* set ctrl*/
60  ctrl.value = value;
61  ctrl.id = id;
62 
63  if (ioctl(s->fd, VIDIOC_S_EXT_CTRLS, &ctrls) < 0)
64  av_log(s->avctx, AV_LOG_WARNING, "Failed to set %s: %s\n", name, strerror(errno));
65  else
66  av_log(s->avctx, AV_LOG_DEBUG, "Encoder: %s = %d\n", name, value);
67 }
68 
69 static inline int v4l2_get_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int *value, const char *name)
70 {
71  struct v4l2_ext_controls ctrls = { { 0 } };
72  struct v4l2_ext_control ctrl = { 0 };
73  int ret;
74 
75  /* set ctrls */
76  ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
77  ctrls.controls = &ctrl;
78  ctrls.count = 1;
79 
80  /* set ctrl*/
81  ctrl.id = id ;
82 
83  ret = ioctl(s->fd, VIDIOC_G_EXT_CTRLS, &ctrls);
84  if (ret < 0) {
85  av_log(s->avctx, AV_LOG_WARNING, "Failed to set %s\n", name);
86  return ret;
87  }
88 
89  *value = ctrl.value;
90 
91  return 0;
92 }
93 
94 static inline unsigned int v4l2_h264_profile_from_ff(int p)
95 {
96  static const struct h264_profile {
97  unsigned int ffmpeg_val;
98  unsigned int v4l2_val;
99  } profile[] = {
100  { FF_PROFILE_H264_CONSTRAINED_BASELINE, MPEG_VIDEO(H264_PROFILE_CONSTRAINED_BASELINE) },
101  { FF_PROFILE_H264_HIGH_444_PREDICTIVE, MPEG_VIDEO(H264_PROFILE_HIGH_444_PREDICTIVE) },
102  { FF_PROFILE_H264_HIGH_422_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_422_INTRA) },
103  { FF_PROFILE_H264_HIGH_444_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_444_INTRA) },
104  { FF_PROFILE_H264_HIGH_10_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_10_INTRA) },
105  { FF_PROFILE_H264_HIGH_422, MPEG_VIDEO(H264_PROFILE_HIGH_422) },
106  { FF_PROFILE_H264_BASELINE, MPEG_VIDEO(H264_PROFILE_BASELINE) },
107  { FF_PROFILE_H264_EXTENDED, MPEG_VIDEO(H264_PROFILE_EXTENDED) },
108  { FF_PROFILE_H264_HIGH_10, MPEG_VIDEO(H264_PROFILE_HIGH_10) },
109  { FF_PROFILE_H264_MAIN, MPEG_VIDEO(H264_PROFILE_MAIN) },
110  { FF_PROFILE_H264_HIGH, MPEG_VIDEO(H264_PROFILE_HIGH) },
111  };
112  int i;
113 
114  for (i = 0; i < FF_ARRAY_ELEMS(profile); i++) {
115  if (profile[i].ffmpeg_val == p)
116  return profile[i].v4l2_val;
117  }
118  return AVERROR(ENOENT);
119 }
120 
121 static inline int v4l2_mpeg4_profile_from_ff(int p)
122 {
123  static const struct mpeg4_profile {
124  unsigned int ffmpeg_val;
125  unsigned int v4l2_val;
126  } profile[] = {
127  { FF_PROFILE_MPEG4_ADVANCED_CODING, MPEG_VIDEO(MPEG4_PROFILE_ADVANCED_CODING_EFFICIENCY) },
128  { FF_PROFILE_MPEG4_ADVANCED_SIMPLE, MPEG_VIDEO(MPEG4_PROFILE_ADVANCED_SIMPLE) },
129  { FF_PROFILE_MPEG4_SIMPLE_SCALABLE, MPEG_VIDEO(MPEG4_PROFILE_SIMPLE_SCALABLE) },
130  { FF_PROFILE_MPEG4_SIMPLE, MPEG_VIDEO(MPEG4_PROFILE_SIMPLE) },
131  { FF_PROFILE_MPEG4_CORE, MPEG_VIDEO(MPEG4_PROFILE_CORE) },
132  };
133  int i;
134 
135  for (i = 0; i < FF_ARRAY_ELEMS(profile); i++) {
136  if (profile[i].ffmpeg_val == p)
137  return profile[i].v4l2_val;
138  }
139  return AVERROR(ENOENT);
140 }
141 
143 {
144  if (s->avctx->max_b_frames)
145  av_log(s->avctx, AV_LOG_WARNING, "Encoder does not support b-frames yet\n");
146 
147  v4l2_set_ext_ctrl(s, MPEG_CID(B_FRAMES), 0, "number of B-frames");
148  v4l2_get_ext_ctrl(s, MPEG_CID(B_FRAMES), &s->avctx->max_b_frames, "number of B-frames");
149  if (s->avctx->max_b_frames == 0)
150  return 0;
151 
152  avpriv_report_missing_feature(s->avctx, "DTS/PTS calculation for V4L2 encoding");
153 
154  return AVERROR_PATCHWELCOME;
155 }
156 
158 {
159  AVCodecContext *avctx = s->avctx;
160  int qmin_cid, qmax_cid, qmin, qmax;
161  int ret, val;
162 
163  /**
164  * requirements
165  */
167  if (ret)
168  return ret;
169 
170  /**
171  * settingss
172  */
173  if (avctx->framerate.num || avctx->framerate.den)
174  v4l2_set_timeperframe(s, avctx->framerate.num, avctx->framerate.den);
175 
176  /* set ext ctrls */
177  v4l2_set_ext_ctrl(s, MPEG_CID(HEADER_MODE), MPEG_VIDEO(HEADER_MODE_SEPARATE), "header mode");
178  v4l2_set_ext_ctrl(s, MPEG_CID(BITRATE) , avctx->bit_rate, "bit rate");
179  v4l2_set_ext_ctrl(s, MPEG_CID(GOP_SIZE), avctx->gop_size,"gop size");
180 
181  av_log(avctx, AV_LOG_DEBUG,
182  "Encoder Context: id (%d), profile (%d), frame rate(%d/%d), number b-frames (%d), "
183  "gop size (%d), bit rate (%"PRId64"), qmin (%d), qmax (%d)\n",
184  avctx->codec_id, avctx->profile, avctx->framerate.num, avctx->framerate.den,
185  avctx->max_b_frames, avctx->gop_size, avctx->bit_rate, avctx->qmin, avctx->qmax);
186 
187  switch (avctx->codec_id) {
188  case AV_CODEC_ID_H264:
189  val = v4l2_h264_profile_from_ff(avctx->profile);
190  if (val < 0)
191  av_log(avctx, AV_LOG_WARNING, "h264 profile not found\n");
192  else
193  v4l2_set_ext_ctrl(s, MPEG_CID(H264_PROFILE), val, "h264 profile");
194  qmin_cid = MPEG_CID(H264_MIN_QP);
195  qmax_cid = MPEG_CID(H264_MAX_QP);
196  qmin = 0;
197  qmax = 51;
198  break;
199  case AV_CODEC_ID_MPEG4:
200  val = v4l2_mpeg4_profile_from_ff(avctx->profile);
201  if (val < 0)
202  av_log(avctx, AV_LOG_WARNING, "mpeg4 profile not found\n");
203  else
204  v4l2_set_ext_ctrl(s, MPEG_CID(MPEG4_PROFILE), val, "mpeg4 profile");
205  qmin_cid = MPEG_CID(MPEG4_MIN_QP);
206  qmax_cid = MPEG_CID(MPEG4_MAX_QP);
207  if (avctx->flags & AV_CODEC_FLAG_QPEL)
208  v4l2_set_ext_ctrl(s, MPEG_CID(MPEG4_QPEL), 1, "qpel");
209  qmin = 1;
210  qmax = 31;
211  break;
212  case AV_CODEC_ID_H263:
213  qmin_cid = MPEG_CID(H263_MIN_QP);
214  qmax_cid = MPEG_CID(H263_MAX_QP);
215  qmin = 1;
216  qmax = 31;
217  break;
218  case AV_CODEC_ID_VP8:
219  qmin_cid = MPEG_CID(VPX_MIN_QP);
220  qmax_cid = MPEG_CID(VPX_MAX_QP);
221  qmin = 0;
222  qmax = 127;
223  break;
224  case AV_CODEC_ID_VP9:
225  qmin_cid = MPEG_CID(VPX_MIN_QP);
226  qmax_cid = MPEG_CID(VPX_MAX_QP);
227  qmin = 0;
228  qmax = 255;
229  break;
230  default:
231  return 0;
232  }
233 
234  if (qmin != avctx->qmin || qmax != avctx->qmax)
235  av_log(avctx, AV_LOG_WARNING, "Encoder adjusted: qmin (%d), qmax (%d)\n", qmin, qmax);
236 
237  v4l2_set_ext_ctrl(s, qmin_cid, qmin, "minimum video quantizer scale");
238  v4l2_set_ext_ctrl(s, qmax_cid, qmax, "maximum video quantizer scale");
239 
240  return 0;
241 }
242 
243 static int v4l2_send_frame(AVCodecContext *avctx, const AVFrame *frame)
244 {
245  V4L2m2mContext *s = ((V4L2m2mPriv*)avctx->priv_data)->context;
246  V4L2Context *const output = &s->output;
247 
248 #ifdef V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME
249  if (frame && frame->pict_type == AV_PICTURE_TYPE_I)
250  v4l2_set_ext_ctrl(s, MPEG_CID(FORCE_KEY_FRAME), 0, "force key frame");
251 #endif
252 
253  return ff_v4l2_context_enqueue_frame(output, frame);
254 }
255 
256 static int v4l2_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
257 {
258  V4L2m2mContext *s = ((V4L2m2mPriv*)avctx->priv_data)->context;
259  V4L2Context *const capture = &s->capture;
260  V4L2Context *const output = &s->output;
261  int ret;
262 
263  if (s->draining)
264  goto dequeue;
265 
266  if (!output->streamon) {
267  ret = ff_v4l2_context_set_status(output, VIDIOC_STREAMON);
268  if (ret) {
269  av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMON failed on output context\n");
270  return ret;
271  }
272  }
273 
274  if (!capture->streamon) {
275  ret = ff_v4l2_context_set_status(capture, VIDIOC_STREAMON);
276  if (ret) {
277  av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMON failed on capture context\n");
278  return ret;
279  }
280  }
281 
282 dequeue:
283  return ff_v4l2_context_dequeue_packet(capture, avpkt);
284 }
285 
287 {
288  V4L2Context *capture, *output;
289  V4L2m2mContext *s;
290  V4L2m2mPriv *priv = avctx->priv_data;
291  int ret;
292 
293  ret = ff_v4l2_m2m_create_context(priv, &s);
294  if (ret < 0)
295  return ret;
296 
297  capture = &s->capture;
298  output = &s->output;
299 
300  /* common settings output/capture */
301  output->height = capture->height = avctx->height;
302  output->width = capture->width = avctx->width;
303 
304  /* output context */
306  output->av_pix_fmt = avctx->pix_fmt;
307 
308  /* capture context */
309  capture->av_codec_id = avctx->codec_id;
310  capture->av_pix_fmt = AV_PIX_FMT_NONE;
311 
312  ret = ff_v4l2_m2m_codec_init(priv);
313  if (ret) {
314  av_log(avctx, AV_LOG_ERROR, "can't configure encoder\n");
315  return ret;
316  }
317  s->avctx = avctx;
318 
319  return v4l2_prepare_encoder(s);
320 }
321 
323 {
324  return ff_v4l2_m2m_codec_end(avctx->priv_data);
325 }
326 
327 #define OFFSET(x) offsetof(V4L2m2mPriv, x)
328 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
329 
330 static const AVOption options[] = {
332  { "num_capture_buffers", "Number of buffers in the capture context",
333  OFFSET(num_capture_buffers), AV_OPT_TYPE_INT, {.i64 = 4 }, 4, INT_MAX, FLAGS },
334  { NULL },
335 };
336 
337 #define M2MENC_CLASS(NAME) \
338  static const AVClass v4l2_m2m_ ## NAME ## _enc_class = { \
339  .class_name = #NAME "_v4l2m2m_encoder", \
340  .item_name = av_default_item_name, \
341  .option = options, \
342  .version = LIBAVUTIL_VERSION_INT, \
343  };
344 
345 #define M2MENC(NAME, LONGNAME, CODEC) \
346  M2MENC_CLASS(NAME) \
347  AVCodec ff_ ## NAME ## _v4l2m2m_encoder = { \
348  .name = #NAME "_v4l2m2m" , \
349  .long_name = NULL_IF_CONFIG_SMALL("V4L2 mem2mem " LONGNAME " encoder wrapper"), \
350  .type = AVMEDIA_TYPE_VIDEO, \
351  .id = CODEC , \
352  .priv_data_size = sizeof(V4L2m2mPriv), \
353  .priv_class = &v4l2_m2m_ ## NAME ##_enc_class, \
354  .init = v4l2_encode_init, \
355  .send_frame = v4l2_send_frame, \
356  .receive_packet = v4l2_receive_packet, \
357  .close = v4l2_encode_close, \
358  .capabilities = AV_CODEC_CAP_HARDWARE | AV_CODEC_CAP_DELAY, \
359  .wrapper_name = "v4l2m2m", \
360  };
361 
362 M2MENC(mpeg4,"MPEG4", AV_CODEC_ID_MPEG4);
363 M2MENC(h263, "H.263", AV_CODEC_ID_H263);
364 M2MENC(h264, "H.264", AV_CODEC_ID_H264);
365 M2MENC(hevc, "HEVC", AV_CODEC_ID_HEVC);
366 M2MENC(vp8, "VP8", AV_CODEC_ID_VP8);
#define FF_PROFILE_H264_MAIN
Definition: avcodec.h:2942
#define FF_PROFILE_MPEG4_SIMPLE
Definition: avcodec.h:2961
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:3108
const char const char void * val
Definition: avisynth_c.h:863
static const AVOption options[]
Definition: v4l2_m2m_enc.c:330
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
AVCodecContext * avctx
Definition: v4l2_m2m.h:52
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1618
int max_b_frames
maximum number of B-frames between non-B-frames Note: The output will be delayed by max_b_frames+1 re...
Definition: avcodec.h:1828
static int v4l2_mpeg4_profile_from_ff(int p)
Definition: v4l2_m2m_enc.c:121
int num
Numerator.
Definition: rational.h:59
#define FLAGS
Definition: v4l2_m2m_enc.c:328
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
int width
Width and height of the frames it produces (in case of a capture context, e.g.
Definition: v4l2_context.h:71
#define MPEG_VIDEO(x)
Definition: v4l2_m2m_enc.c:35
#define FF_PROFILE_MPEG4_SIMPLE_SCALABLE
Definition: avcodec.h:2962
int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv)
Releases all the codec resources if all AVBufferRefs have been returned to the ctx.
Definition: v4l2_m2m.c:336
int ff_v4l2_context_dequeue_packet(V4L2Context *ctx, AVPacket *pkt)
Dequeues a buffer from a V4L2Context to an AVPacket.
Definition: v4l2_context.c:625
int profile
profile
Definition: avcodec.h:2901
static int v4l2_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Definition: v4l2_m2m_enc.c:256
static av_cold int v4l2_encode_init(AVCodecContext *avctx)
Definition: v4l2_m2m_enc.c:286
#define FF_PROFILE_H264_HIGH_444_PREDICTIVE
Definition: avcodec.h:2952
int ff_v4l2_m2m_codec_init(V4L2m2mPriv *priv)
Probes the video nodes looking for the required codec capabilities.
Definition: v4l2_m2m.c:357
enum AVCodecID av_codec_id
AVCodecID corresponding to this buffer context.
Definition: v4l2_context.h:59
#define FF_PROFILE_H264_BASELINE
Definition: avcodec.h:2940
int ff_v4l2_m2m_create_context(V4L2m2mPriv *priv, V4L2m2mContext **s)
Allocate a new context and references for a V4L2 M2M instance.
Definition: v4l2_m2m.c:397
#define av_cold
Definition: attributes.h:82
#define FF_PROFILE_MPEG4_CORE
Definition: avcodec.h:2963
AVOptions.
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce output
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
#define OFFSET(x)
Definition: v4l2_m2m_enc.c:327
static int v4l2_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Definition: v4l2_m2m_enc.c:243
static void v4l2_set_timeperframe(V4L2m2mContext *s, unsigned int num, unsigned int den)
Definition: v4l2_m2m_enc.c:37
#define FF_PROFILE_H264_EXTENDED
Definition: avcodec.h:2943
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static av_cold int v4l2_encode_close(AVCodecContext *avctx)
Definition: v4l2_m2m_enc.c:322
int qmax
maximum quantizer
Definition: avcodec.h:2417
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
#define FF_PROFILE_H264_HIGH_422
Definition: avcodec.h:2948
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1648
#define FF_PROFILE_H264_HIGH
Definition: avcodec.h:2944
enum AVPixelFormat av_pix_fmt
AVPixelFormat corresponding to this buffer context.
Definition: v4l2_context.h:53
int streamon
Whether the stream has been started (VIDIOC_STREAMON has been sent).
Definition: v4l2_context.h:87
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
static int v4l2_get_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int *value, const char *name)
Definition: v4l2_m2m_enc.c:69
static int v4l2_check_b_frame_support(V4L2m2mContext *s)
Definition: v4l2_m2m_enc.c:142
int width
picture width / height.
Definition: avcodec.h:1741
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
#define FF_ARRAY_ELEMS(a)
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
int ff_v4l2_context_set_status(V4L2Context *ctx, uint32_t cmd)
Sets the status of a V4L2Context.
Definition: v4l2_context.c:541
V4L2Context capture
Definition: v4l2_m2m.h:48
Libavcodec external API header.
#define FF_PROFILE_H264_HIGH_422_INTRA
Definition: avcodec.h:2949
enum AVCodecID codec_id
Definition: avcodec.h:1578
#define M2MENC(NAME, LONGNAME, CODEC)
Definition: v4l2_m2m_enc.c:345
main external API structure.
Definition: avcodec.h:1568
#define FF_PROFILE_MPEG4_ADVANCED_SIMPLE
Definition: avcodec.h:2976
int qmin
minimum quantizer
Definition: avcodec.h:2410
#define FF_PROFILE_H264_HIGH_10_INTRA
Definition: avcodec.h:2946
#define FF_PROFILE_MPEG4_ADVANCED_CODING
Definition: avcodec.h:2972
mfxU16 profile
Definition: qsvenc.c:44
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
V4L2Context output
Definition: v4l2_m2m.h:49
#define AV_CODEC_FLAG_QPEL
Use qpel MC.
Definition: avcodec.h:865
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1763
int ff_v4l2_context_enqueue_frame(V4L2Context *ctx, const AVFrame *frame)
Enqueues a buffer to a V4L2Context from an AVFrame.
Definition: v4l2_context.c:555
int den
Denominator.
Definition: rational.h:60
#define MPEG_CID(x)
Definition: v4l2_m2m_enc.c:34
static int v4l2_prepare_encoder(V4L2m2mContext *s)
Definition: v4l2_m2m_enc.c:157
void * priv_data
Definition: avcodec.h:1595
pixel format definitions
#define V4L_M2M_DEFAULT_OPTS
Definition: v4l2_m2m.h:39
static unsigned int v4l2_h264_profile_from_ff(int p)
Definition: v4l2_m2m_enc.c:94
#define FF_PROFILE_H264_HIGH_444_INTRA
Definition: avcodec.h:2953
#define FF_PROFILE_H264_CONSTRAINED_BASELINE
Definition: avcodec.h:2941
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
#define FF_PROFILE_H264_HIGH_10
Definition: avcodec.h:2945
enum AVCodecID id
This structure stores compressed data.
Definition: avcodec.h:1457
static void v4l2_set_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int value, const char *name)
Definition: v4l2_m2m_enc.c:49
enum v4l2_buf_type type
Type of this buffer context.
Definition: v4l2_context.h:47
const char * name
Definition: opengl_enc.c:102