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Line	Branch	Exec	Source
1			/*
2			* RTP parser for HEVC/H.265 payload format (draft version 6)
3			* Copyright (c) 2014 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/avassert.h"
23			#include "libavutil/avstring.h"
24			#include "libavutil/mem.h"
25
26			#include "avformat.h"
27			#include "internal.h"
28			#include "rtpdec.h"
29			#include "rtpdec_formats.h"
30
31			#define RTP_HEVC_PAYLOAD_HEADER_SIZE 2
32			#define RTP_HEVC_FU_HEADER_SIZE 1
33			#define RTP_HEVC_DONL_FIELD_SIZE 2
34			#define RTP_HEVC_DOND_FIELD_SIZE 1
35			#define RTP_HEVC_AP_NALU_LENGTH_FIELD_SIZE 2
36			#define HEVC_SPECIFIED_NAL_UNIT_TYPES 48
37
38			/* SDP out-of-band signaling data */
39			struct PayloadContext {
40			int using_donl_field;
41			int profile_id;
42			uint8_t *sps, *pps, *vps, *sei;
43			int sps_size, pps_size, vps_size, sei_size;
44			};
45
46			static const uint8_t start_sequence[] = { 0x00, 0x00, 0x00, 0x01 };
47
48		✗	static av_cold int hevc_sdp_parse_fmtp_config(AVFormatContext *s,
49			AVStream *stream,
50			PayloadContext *hevc_data,
51			const char *attr, const char *value)
52			{
53			/* profile-space: 0-3 */
54			/* profile-id: 0-31 */
55		✗	if (!strcmp(attr, "profile-id")) {
56		✗	hevc_data->profile_id = atoi(value);
57		✗	av_log(s, AV_LOG_TRACE, "SDP: found profile-id: %d\n", hevc_data->profile_id);
58			}
59
60			/* tier-flag: 0-1 */
61			/* level-id: 0-255 */
62			/* interop-constraints: [base16] */
63			/* profile-compatibility-indicator: [base16] */
64			/* sprop-sub-layer-id: 0-6, defines highest possible value for TID, default: 6 */
65			/* recv-sub-layer-id: 0-6 */
66			/* max-recv-level-id: 0-255 */
67			/* tx-mode: MSM,SSM */
68			/* sprop-vps: [base64] */
69			/* sprop-sps: [base64] */
70			/* sprop-pps: [base64] */
71			/* sprop-sei: [base64] */
72		✗	if (!strcmp(attr, "sprop-vps") || !strcmp(attr, "sprop-sps") ||
73		✗	!strcmp(attr, "sprop-pps") || !strcmp(attr, "sprop-sei")) {
74		✗	uint8_t **data_ptr = NULL;
75		✗	int *size_ptr = NULL;
76		✗	if (!strcmp(attr, "sprop-vps")) {
77		✗	data_ptr = &hevc_data->vps;
78		✗	size_ptr = &hevc_data->vps_size;
79		✗	} else if (!strcmp(attr, "sprop-sps")) {
80		✗	data_ptr = &hevc_data->sps;
81		✗	size_ptr = &hevc_data->sps_size;
82		✗	} else if (!strcmp(attr, "sprop-pps")) {
83		✗	data_ptr = &hevc_data->pps;
84		✗	size_ptr = &hevc_data->pps_size;
85		✗	} else if (!strcmp(attr, "sprop-sei")) {
86		✗	data_ptr = &hevc_data->sei;
87		✗	size_ptr = &hevc_data->sei_size;
88			} else
89		✗	av_assert0(0);
90
91		✗	ff_h264_parse_sprop_parameter_sets(s, data_ptr,
92			size_ptr, value);
93			}
94
95			/* max-lsr, max-lps, max-cpb, max-dpb, max-br, max-tr, max-tc */
96			/* max-fps */
97
98			/* sprop-max-don-diff: 0-32767
99
100			When the RTP stream depends on one or more other RTP
101			streams (in this case tx-mode MUST be equal to "MSM" and
102			MSM is in use), this parameter MUST be present and the
103			value MUST be greater than 0.
104			*/
105		✗	if (!strcmp(attr, "sprop-max-don-diff")) {
106		✗	if (atoi(value) > 0)
107		✗	hevc_data->using_donl_field = 1;
108		✗	av_log(s, AV_LOG_TRACE, "Found sprop-max-don-diff in SDP, DON field usage is: %d\n",
109			hevc_data->using_donl_field);
110			}
111
112			/* sprop-depack-buf-nalus: 0-32767 */
113		✗	if (!strcmp(attr, "sprop-depack-buf-nalus")) {
114		✗	if (atoi(value) > 0)
115		✗	hevc_data->using_donl_field = 1;
116		✗	av_log(s, AV_LOG_TRACE, "Found sprop-depack-buf-nalus in SDP, DON field usage is: %d\n",
117			hevc_data->using_donl_field);
118			}
119
120			/* sprop-depack-buf-bytes: 0-4294967295 */
121			/* depack-buf-cap */
122			/* sprop-segmentation-id: 0-3 */
123			/* sprop-spatial-segmentation-idc: [base16] */
124			/* dec-parallel-ca: */
125			/* include-dph */
126
127		✗	return 0;
128			}
129
130		✗	static av_cold int hevc_parse_sdp_line(AVFormatContext *ctx, int st_index,
131			PayloadContext *hevc_data, const char *line)
132			{
133			AVStream *current_stream;
134			AVCodecParameters *par;
135		✗	const char *sdp_line_ptr = line;
136
137		✗	if (st_index < 0)
138		✗	return 0;
139
140		✗	current_stream = ctx->streams[st_index];
141		✗	par = current_stream->codecpar;
142
143		✗	if (av_strstart(sdp_line_ptr, "framesize:", &sdp_line_ptr)) {
144		✗	ff_h264_parse_framesize(par, sdp_line_ptr);
145		✗	} else if (av_strstart(sdp_line_ptr, "fmtp:", &sdp_line_ptr)) {
146		✗	int ret = ff_parse_fmtp(ctx, current_stream, hevc_data, sdp_line_ptr,
147			hevc_sdp_parse_fmtp_config);
148		✗	if (hevc_data->vps_size || hevc_data->sps_size ||
149		✗	hevc_data->pps_size || hevc_data->sei_size) {
150		✗	par->extradata_size = hevc_data->vps_size + hevc_data->sps_size +
151		✗	hevc_data->pps_size + hevc_data->sei_size;
152		✗	if ((ret = ff_alloc_extradata(par, par->extradata_size)) >= 0) {
153		✗	int pos = 0;
154		✗	memcpy(par->extradata + pos, hevc_data->vps, hevc_data->vps_size);
155		✗	pos += hevc_data->vps_size;
156		✗	memcpy(par->extradata + pos, hevc_data->sps, hevc_data->sps_size);
157		✗	pos += hevc_data->sps_size;
158		✗	memcpy(par->extradata + pos, hevc_data->pps, hevc_data->pps_size);
159		✗	pos += hevc_data->pps_size;
160		✗	memcpy(par->extradata + pos, hevc_data->sei, hevc_data->sei_size);
161			}
162
163		✗	av_freep(&hevc_data->vps);
164		✗	av_freep(&hevc_data->sps);
165		✗	av_freep(&hevc_data->pps);
166		✗	av_freep(&hevc_data->sei);
167		✗	hevc_data->vps_size = 0;
168		✗	hevc_data->sps_size = 0;
169		✗	hevc_data->pps_size = 0;
170		✗	hevc_data->sei_size = 0;
171			}
172		✗	return ret;
173			}
174
175		✗	return 0;
176			}
177
178		✗	static int hevc_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_hevc_ctx,
179			AVStream *st, AVPacket *pkt, uint32_t *timestamp,
180			const uint8_t *buf, int len, uint16_t seq,
181			int flags)
182			{
183		✗	const uint8_t *rtp_pl = buf;
184			int tid, lid, nal_type;
185			int first_fragment, last_fragment, fu_type;
186			uint8_t new_nal_header[2];
187		✗	int res = 0;
188
189			/* sanity check for size of input packet: 1 byte payload at least */
190		✗	if (len < RTP_HEVC_PAYLOAD_HEADER_SIZE + 1) {
191		✗	av_log(ctx, AV_LOG_ERROR, "Too short RTP/HEVC packet, got %d bytes\n", len);
192		✗	return AVERROR_INVALIDDATA;
193			}
194
195			/*
196			* decode the HEVC payload header according to section 4 of draft version 6:
197			*
198			* 0 1
199			* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
200			* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
201			* |F| Type | LayerId | TID |
202			* +-------------+-----------------+
203			*
204			* Forbidden zero (F): 1 bit
205			* NAL unit type (Type): 6 bits
206			* NUH layer ID (LayerId): 6 bits
207			* NUH temporal ID plus 1 (TID): 3 bits
208			*/
209		✗	nal_type = (buf[0] >> 1) & 0x3f;
210		✗	lid = ((buf[0] << 5) & 0x20) | ((buf[1] >> 3) & 0x1f);
211		✗	tid = buf[1] & 0x07;
212
213			/* sanity check for correct layer ID */
214		✗	if (lid) {
215			/* future scalable or 3D video coding extensions */
216		✗	avpriv_report_missing_feature(ctx, "Multi-layer HEVC coding");
217		✗	return AVERROR_PATCHWELCOME;
218			}
219
220			/* sanity check for correct temporal ID */
221		✗	if (!tid) {
222		✗	av_log(ctx, AV_LOG_ERROR, "Illegal temporal ID in RTP/HEVC packet\n");
223		✗	return AVERROR_INVALIDDATA;
224			}
225
226			/* sanity check for correct NAL unit type */
227		✗	if (nal_type > 50) {
228		✗	av_log(ctx, AV_LOG_ERROR, "Unsupported (HEVC) NAL type (%d)\n", nal_type);
229		✗	return AVERROR_INVALIDDATA;
230			}
231
232		✗	switch (nal_type) {
233			/* video parameter set (VPS) */
234		✗	case 32:
235			/* sequence parameter set (SPS) */
236			case 33:
237			/* picture parameter set (PPS) */
238			case 34:
239			/* supplemental enhancement information (SEI) */
240			case 39:
241			/* single NAL unit packet */
242			default:
243			/* create A/V packet */
244		✗	if ((res = av_new_packet(pkt, sizeof(start_sequence) + len)) < 0)
245		✗	return res;
246			/* A/V packet: copy start sequence */
247		✗	memcpy(pkt->data, start_sequence, sizeof(start_sequence));
248			/* A/V packet: copy NAL unit data */
249		✗	memcpy(pkt->data + sizeof(start_sequence), buf, len);
250
251		✗	break;
252			/* aggregated packet (AP) - with two or more NAL units */
253		✗	case 48:
254			/* pass the HEVC payload header */
255		✗	buf += RTP_HEVC_PAYLOAD_HEADER_SIZE;
256		✗	len -= RTP_HEVC_PAYLOAD_HEADER_SIZE;
257
258			/* pass the HEVC DONL field */
259		✗	if (rtp_hevc_ctx->using_donl_field) {
260		✗	buf += RTP_HEVC_DONL_FIELD_SIZE;
261		✗	len -= RTP_HEVC_DONL_FIELD_SIZE;
262			}
263
264		✗	res = ff_h264_handle_aggregated_packet(ctx, rtp_hevc_ctx, pkt, buf, len,
265		✗	rtp_hevc_ctx->using_donl_field ?
266			RTP_HEVC_DOND_FIELD_SIZE : 0,
267			NULL, 0);
268		✗	if (res < 0)
269		✗	return res;
270		✗	break;
271			/* fragmentation unit (FU) */
272		✗	case 49:
273			/* pass the HEVC payload header */
274		✗	buf += RTP_HEVC_PAYLOAD_HEADER_SIZE;
275		✗	len -= RTP_HEVC_PAYLOAD_HEADER_SIZE;
276
277			/*
278			* decode the FU header
279			*
280			* 0 1 2 3 4 5 6 7
281			* +-+-+-+-+-+-+-+-+
282			* |S|E| FuType |
283			* +---------------+
284			*
285			* Start fragment (S): 1 bit
286			* End fragment (E): 1 bit
287			* FuType: 6 bits
288			*/
289		✗	first_fragment = buf[0] & 0x80;
290		✗	last_fragment = buf[0] & 0x40;
291		✗	fu_type = buf[0] & 0x3f;
292
293			/* pass the HEVC FU header */
294		✗	buf += RTP_HEVC_FU_HEADER_SIZE;
295		✗	len -= RTP_HEVC_FU_HEADER_SIZE;
296
297			/* pass the HEVC DONL field */
298		✗	if (rtp_hevc_ctx->using_donl_field) {
299		✗	buf += RTP_HEVC_DONL_FIELD_SIZE;
300		✗	len -= RTP_HEVC_DONL_FIELD_SIZE;
301			}
302
303		✗	av_log(ctx, AV_LOG_TRACE, " FU type %d with %d bytes\n", fu_type, len);
304
305			/* sanity check for size of input packet: 1 byte payload at least */
306		✗	if (len <= 0) {
307		✗	if (len < 0) {
308		✗	av_log(ctx, AV_LOG_ERROR,
309			"Too short RTP/HEVC packet, got %d bytes of NAL unit type %d\n",
310			len, nal_type);
311		✗	return AVERROR_INVALIDDATA;
312			} else {
313		✗	return AVERROR(EAGAIN);
314			}
315			}
316
317		✗	if (first_fragment && last_fragment) {
318		✗	av_log(ctx, AV_LOG_ERROR, "Illegal combination of S and E bit in RTP/HEVC packet\n");
319		✗	return AVERROR_INVALIDDATA;
320			}
321
322		✗	new_nal_header[0] = (rtp_pl[0] & 0x81) | (fu_type << 1);
323		✗	new_nal_header[1] = rtp_pl[1];
324
325		✗	res = ff_h264_handle_frag_packet(pkt, buf, len, first_fragment,
326			new_nal_header, sizeof(new_nal_header));
327
328		✗	break;
329			/* PACI packet */
330		✗	case 50:
331			/* Temporal scalability control information (TSCI) */
332		✗	avpriv_report_missing_feature(ctx, "PACI packets for RTP/HEVC");
333		✗	res = AVERROR_PATCHWELCOME;
334		✗	break;
335			}
336
337		✗	pkt->stream_index = st->index;
338
339		✗	return res;
340			}
341
342			const RTPDynamicProtocolHandler ff_hevc_dynamic_handler = {
343			.enc_name = "H265",
344			.codec_type = AVMEDIA_TYPE_VIDEO,
345			.codec_id = AV_CODEC_ID_HEVC,
346			.need_parsing = AVSTREAM_PARSE_FULL,
347			.priv_data_size = sizeof(PayloadContext),
348			.parse_sdp_a_line = hevc_parse_sdp_line,
349			.parse_packet = hevc_handle_packet,
350			};
351