FFmpeg coverage

Line	Branch	Exec	Source
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 {
30			AVIOContext *buf;
31			uint32_t timestamp;
32			};
33
34		✗	static av_cold int vp9_init(AVFormatContext *ctx, int st_index,
35			PayloadContext *data)
36			{
37		✗	av_log(ctx, AV_LOG_WARNING,
38			"RTP/VP9 support is still experimental\n");
39
40		✗	return 0;
41			}
42
43		✗	static int vp9_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_vp9_ctx,
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 */
99		✗	buf += RTP_VP9_DESC_REQUIRED_SIZE;
100		✗	len -= RTP_VP9_DESC_REQUIRED_SIZE;
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
328		✗	static void vp9_close_context(PayloadContext *vp9)
329			{
330		✗	ffio_free_dyn_buf(&vp9->buf);
331		✗	}
332
333			const RTPDynamicProtocolHandler ff_vp9_dynamic_handler = {
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,
340			.parse_packet = vp9_handle_packet
341			};
342