FFmpeg  4.3
rtpdec_vp9.c
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1 /*
2  * RTP parser for VP9 payload format (draft version 02) - experimental
3  * Copyright (c) 2015 Thomas Volkert <thomas@homer-conferencing.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 
24 #include "avio_internal.h"
25 #include "rtpdec_formats.h"
26 
27 #define RTP_VP9_DESC_REQUIRED_SIZE 1
28 
29 struct PayloadContext {
31  uint32_t timestamp;
32 };
33 
34 static av_cold int vp9_init(AVFormatContext *ctx, int st_index,
36 {
38  "RTP/VP9 support is still experimental\n");
39 
40  return 0;
41 }
42 
44  AVStream *st, AVPacket *pkt, uint32_t *timestamp,
45  const uint8_t *buf, int len, uint16_t seq,
46  int flags)
47 {
48  int has_pic_id, has_layer_idc, has_ref_idc, has_ss_data;
49  av_unused int pic_id = 0, non_key_frame = 0, inter_picture_layer_frame;
50  av_unused int layer_temporal = -1, layer_spatial = -1, layer_quality = -1;
51  int ref_fields = 0, has_ref_field_ext_pic_id = 0;
52  int first_fragment, last_fragment;
53  int rtp_m;
54  int res = 0;
55 
56  /* drop data of previous packets in case of non-continuous (lossy) packet stream */
57  if (rtp_vp9_ctx->buf && rtp_vp9_ctx->timestamp != *timestamp)
58  ffio_free_dyn_buf(&rtp_vp9_ctx->buf);
59 
60  /* sanity check for size of input packet: 1 byte payload at least */
61  if (len < RTP_VP9_DESC_REQUIRED_SIZE + 1) {
62  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet, got %d bytes\n", len);
63  return AVERROR_INVALIDDATA;
64  }
65 
66  /*
67  * decode the required VP9 payload descriptor according to section 4.2 of the spec.:
68  *
69  * 0 1 2 3 4 5 6 7
70  * +-+-+-+-+-+-+-+-+
71  * |I|P|L|F|B|E|V|-| (REQUIRED)
72  * +-+-+-+-+-+-+-+-+
73  *
74  * I: PictureID present
75  * P: Inter-picture predicted layer frame
76  * L: Layer indices present
77  * F: Flexible mode
78  * B: Start of VP9 frame
79  * E: End of picture
80  * V: Scalability Structure (SS) present
81  */
82  has_pic_id = !!(buf[0] & 0x80);
83  inter_picture_layer_frame = !!(buf[0] & 0x40);
84  has_layer_idc = !!(buf[0] & 0x20);
85  has_ref_idc = !!(buf[0] & 0x10);
86  first_fragment = !!(buf[0] & 0x08);
87  last_fragment = !!(buf[0] & 0x04);
88  has_ss_data = !!(buf[0] & 0x02);
89 
90  rtp_m = !!(flags & RTP_FLAG_MARKER);
91 
92  /* sanity check for markers: B should always be equal to the RTP M marker */
93  if (last_fragment != rtp_m) {
94  av_log(ctx, AV_LOG_ERROR, "Invalid combination of B and M marker (%d != %d)\n", last_fragment, rtp_m);
95  return AVERROR_INVALIDDATA;
96  }
97 
98  /* pass the extensions field */
101 
102  /*
103  * decode the 1-byte/2-byte picture ID:
104  *
105  * 0 1 2 3 4 5 6 7
106  * +-+-+-+-+-+-+-+-+
107  * I: |M|PICTURE ID | (RECOMMENDED)
108  * +-+-+-+-+-+-+-+-+
109  * M: | EXTENDED PID | (RECOMMENDED)
110  * +-+-+-+-+-+-+-+-+
111  *
112  * M: The most significant bit of the first octet is an extension flag.
113  * PictureID: 8 or 16 bits including the M bit.
114  */
115  if (has_pic_id) {
116  /* check for 1-byte or 2-byte picture index */
117  if (buf[0] & 0x80) {
118  if (len < 2) {
119  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
120  return AVERROR_INVALIDDATA;
121  }
122  pic_id = AV_RB16(buf) & 0x7fff;
123  buf += 2;
124  len -= 2;
125  } else {
126  pic_id = buf[0] & 0x7f;
127  buf++;
128  len--;
129  }
130  }
131 
132  /*
133  * decode layer indices
134  *
135  * 0 1 2 3 4 5 6 7
136  * +-+-+-+-+-+-+-+-+
137  * L: | T | S | Q | R | (CONDITIONALLY RECOMMENDED)
138  * +-+-+-+-+-+-+-+-+
139  *
140  * T, S and Q are 2-bit indices for temporal, spatial, and quality layers.
141  * If "F" is set in the initial octet, R is 2 bits representing the number
142  * of reference fields this frame refers to.
143  */
144  if (has_layer_idc) {
145  if (len < 1) {
146  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
147  return AVERROR_INVALIDDATA;
148  }
149  layer_temporal = buf[0] & 0xC0;
150  layer_spatial = buf[0] & 0x30;
151  layer_quality = buf[0] & 0x0C;
152  if (has_ref_idc) {
153  ref_fields = buf[0] & 0x03;
154  if (ref_fields)
155  non_key_frame = 1;
156  }
157  buf++;
158  len--;
159  }
160 
161  /*
162  * decode the reference fields
163  *
164  * 0 1 2 3 4 5 6 7
165  * +-+-+-+-+-+-+-+-+ -\
166  * F: | PID |X| RS| RQ| (OPTIONAL) .
167  * +-+-+-+-+-+-+-+-+ . - R times
168  * X: | EXTENDED PID | (OPTIONAL) .
169  * +-+-+-+-+-+-+-+-+ -/
170  *
171  * PID: The relative Picture ID referred to by this frame.
172  * RS and RQ: The spatial and quality layer IDs.
173  * X: 1 if this layer index has an extended relative Picture ID.
174  */
175  if (has_ref_idc) {
176  while (ref_fields) {
177  if (len < 1) {
178  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
179  return AVERROR_INVALIDDATA;
180  }
181 
182  has_ref_field_ext_pic_id = buf[0] & 0x10;
183 
184  /* pass ref. field */
185  if (has_ref_field_ext_pic_id) {
186  if (len < 2) {
187  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
188  return AVERROR_INVALIDDATA;
189  }
190 
191  /* ignore ref. data */
192 
193  buf += 2;
194  len -= 2;
195  } else {
196 
197  /* ignore ref. data */
198 
199  buf++;
200  len--;
201  }
202  ref_fields--;
203  }
204  }
205 
206  /*
207  * decode the scalability structure (SS)
208  *
209  * 0 1 2 3 4 5 6 7
210  * +-+-+-+-+-+-+-+-+
211  * V: | PATTERN LENGTH|
212  * +-+-+-+-+-+-+-+-+ -\
213  * | T | S | Q | R | (OPTIONAL) .
214  * +-+-+-+-+-+-+-+-+ -\ .
215  * | PID |X| RS| RQ| (OPTIONAL) . . - PAT. LEN. times
216  * +-+-+-+-+-+-+-+-+ . - R times .
217  * X: | EXTENDED PID | (OPTIONAL) . .
218  * +-+-+-+-+-+-+-+-+ -/ -/
219  *
220  * PID: The relative Picture ID referred to by this frame.
221  * RS and RQ: The spatial and quality layer IDs.
222  * X: 1 if this layer index has an extended relative Picture ID.
223  */
224  if (has_ss_data) {
225  int n_s, y, g, i;
226  if (len < 1) {
227  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
228  return AVERROR_INVALIDDATA;
229  }
230  n_s = buf[0] >> 5;
231  y = !!(buf[0] & 0x10);
232  g = !!(buf[0] & 0x08);
233  buf++;
234  len--;
235  if (n_s > 0) {
236  avpriv_report_missing_feature(ctx, "VP9 scalability structure with multiple layers");
237  return AVERROR_PATCHWELCOME;
238  }
239  if (y) {
240  if (len < 4 * (n_s + 1)) {
241  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
242  return AVERROR_INVALIDDATA;
243  }
244  for (i = 0; i < n_s + 1; i++) {
245  av_unused int w, h;
246  w = AV_RB16(buf);
247  h = AV_RB16(buf + 2);
248  buf += 4;
249  len -= 4;
250  }
251  }
252  if (g) {
253  int n_g;
254  if (len < 1) {
255  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
256  return AVERROR_INVALIDDATA;
257  }
258  n_g = buf[0];
259  buf++;
260  len--;
261  for (i = 0; i < n_g; i++) {
262  av_unused int t, u, r, j;
263  if (len < 1) {
264  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
265  return AVERROR_INVALIDDATA;
266  }
267  t = buf[0] >> 5;
268  u = !!(buf[0] & 0x10);
269  r = (buf[0] >> 2) & 0x03;
270  buf++;
271  len--;
272  if (len < r) {
273  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
274  return AVERROR_INVALIDDATA;
275  }
276  for (j = 0; j < r; j++) {
277  av_unused int p_diff = buf[0];
278  buf++;
279  len--;
280  }
281  }
282  }
283  }
284 
285  /*
286  * decode the VP9 payload header
287  *
288  * spec. is tbd
289  */
290  //XXX: implement when specified
291 
292  /* sanity check: 1 byte payload as minimum */
293  if (len < 1) {
294  av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
295  return AVERROR_INVALIDDATA;
296  }
297 
298  /* start frame buffering with new dynamic buffer */
299  if (!rtp_vp9_ctx->buf) {
300  /* sanity check: a new frame should have started */
301  if (first_fragment) {
302  res = avio_open_dyn_buf(&rtp_vp9_ctx->buf);
303  if (res < 0)
304  return res;
305  /* update the timestamp in the frame packet with the one from the RTP packet */
306  rtp_vp9_ctx->timestamp = *timestamp;
307  } else {
308  /* frame not started yet, need more packets */
309  return AVERROR(EAGAIN);
310  }
311  }
312 
313  /* write the fragment to the dyn. buffer */
314  avio_write(rtp_vp9_ctx->buf, buf, len);
315 
316  /* do we need more fragments? */
317  if (!last_fragment)
318  return AVERROR(EAGAIN);
319 
320  /* close frame buffering and create resulting A/V packet */
321  res = ff_rtp_finalize_packet(pkt, &rtp_vp9_ctx->buf, st->index);
322  if (res < 0)
323  return res;
324 
325  return 0;
326 }
327 
329 {
330  ffio_free_dyn_buf(&vp9->buf);
331 }
332 
334  .enc_name = "VP9",
335  .codec_type = AVMEDIA_TYPE_VIDEO,
336  .codec_id = AV_CODEC_ID_VP9,
337  .priv_data_size = sizeof(PayloadContext),
338  .init = vp9_init,
339  .close = vp9_close_context,
341 };
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
vp9_handle_packet
static int vp9_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_vp9_ctx, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Definition: rtpdec_vp9.c:43
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
vp9_init
static av_cold int vp9_init(AVFormatContext *ctx, int st_index, PayloadContext *data)
Definition: rtpdec_vp9.c:34
AVERROR
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
u
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:262
rtpdec_formats.h
vp9_close_context
static void vp9_close_context(PayloadContext *vp9)
Definition: rtpdec_vp9.c:328
av_unused
#define av_unused
Definition: attributes.h:131
RTP_FLAG_MARKER
#define RTP_FLAG_MARKER
RTP marker bit was set for this packet.
Definition: rtpdec.h:93
data
const char data[16]
Definition: mxf.c:91
AV_RB16
#define AV_RB16
Definition: intreadwrite.h:53
ff_rtp_finalize_packet
int ff_rtp_finalize_packet(AVPacket *pkt, AVIOContext **dyn_buf, int stream_idx)
Close the dynamic buffer and make a packet from it.
Definition: rtpdec.c:925
PayloadContext::timestamp
uint32_t timestamp
current frame timestamp
Definition: rtpdec_ac3.c:31
RTPDynamicProtocolHandler::enc_name
const char * enc_name
Definition: rtpdec.h:116
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_cold
#define av_cold
Definition: attributes.h:90
avio_open_dyn_buf
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1356
intreadwrite.h
g
const char * g
Definition: vf_curves.c:115
AV_CODEC_ID_VP9
@ AV_CODEC_ID_VP9
Definition: codec_id.h:217
ctx
AVFormatContext * ctx
Definition: movenc.c:48
parse_packet
static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index, int flush)
Parse a packet, add all split parts to parse_queue.
Definition: utils.c:1443
AVFormatContext
Format I/O context.
Definition: avformat.h:1335
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
avpriv_report_missing_feature
void avpriv_report_missing_feature(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:213
r
#define r
Definition: input.c:40
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
avio_internal.h
uint8_t
uint8_t
Definition: audio_convert.c:194
len
int len
Definition: vorbis_enc_data.h:452
ffio_free_dyn_buf
void ffio_free_dyn_buf(AVIOContext **s)
Free a dynamic buffer.
Definition: aviobuf.c:1431
AVStream
Stream structure.
Definition: avformat.h:865
RTP_VP9_DESC_REQUIRED_SIZE
#define RTP_VP9_DESC_REQUIRED_SIZE
Definition: rtpdec_vp9.c:27
w
FFmpeg Automated Testing Environment ************************************Introduction Using FATE from your FFmpeg source directory Submitting the results to the FFmpeg result aggregation server Uploading new samples to the fate suite FATE makefile targets and variables Makefile targets Makefile variables Examples Introduction **************FATE is an extended regression suite on the client side and a means for results aggregation and presentation on the server side The first part of this document explains how you can use FATE from your FFmpeg source directory to test your ffmpeg binary The second part describes how you can run FATE to submit the results to FFmpeg’s FATE server In any way you can have a look at the publicly viewable FATE results by visiting this as it can be seen if some test on some platform broke with their recent contribution This usually happens on the platforms the developers could not test on The second part of this document describes how you can run FATE to submit your results to FFmpeg’s FATE server If you want to submit your results be sure to check that your combination of OS and compiler is not already listed on the above mentioned website In the third part you can find a comprehensive listing of FATE makefile targets and variables Using FATE from your FFmpeg source directory **********************************************If you want to run FATE on your machine you need to have the samples in place You can get the samples via the build target fate rsync Use this command from the top level source this will cause FATE to fail NOTE To use a custom wrapper to run the pass ‘ target exec’ to ‘configure’ or set the TARGET_EXEC Make variable Submitting the results to the FFmpeg result aggregation server ****************************************************************To submit your results to the server you should run fate through the shell script ‘tests fate sh’ from the FFmpeg sources This script needs to be invoked with a configuration file as its first argument tests fate sh path to fate_config A configuration file template with comments describing the individual configuration variables can be found at ‘doc fate_config sh template’ Create a configuration that suits your based on the configuration template The ‘slot’ configuration variable can be any string that is not yet but it is suggested that you name it adhering to the following pattern ‘ARCH OS COMPILER COMPILER VERSION’ The configuration file itself will be sourced in a shell therefore all shell features may be used This enables you to setup the environment as you need it for your build For your first test runs the ‘fate_recv’ variable should be empty or commented out This will run everything as normal except that it will omit the submission of the results to the server The following files should be present in $workdir as specified in the configuration it may help to try out the ‘ssh’ command with one or more ‘ v’ options You should get detailed output concerning your SSH configuration and the authentication process The only thing left is to automate the execution of the fate sh script and the synchronisation of the samples directory Uploading new samples to the fate suite *****************************************If you need a sample uploaded send a mail to samples request This is for developers who have an account on the fate suite server If you upload new please make sure they are as small as space on each network bandwidth and so on benefit from smaller test cases Also keep in mind older checkouts use existing sample that means in practice generally do not remove or overwrite files as it likely would break older checkouts or releases Also all needed samples for a commit should be ideally before the push If you need an account for frequently uploading samples or you wish to help others by doing that send a mail to ffmpeg devel rsync vauL Duo ug o o w
Definition: fate.txt:150
PayloadContext::buf
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:183
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:866
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
ff_vp9_dynamic_handler
const RTPDynamicProtocolHandler ff_vp9_dynamic_handler
Definition: rtpdec_vp9.c:333
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPacket
This structure stores compressed data.
Definition: packet.h:332
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:564
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
h
h
Definition: vp9dsp_template.c:2038
PayloadContext
RTP/JPEG specific private data.
Definition: rdt.c:83
RTPDynamicProtocolHandler
Definition: rtpdec.h:115