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/base64.h"
25 #include "libavcodec/get_bits.h"
26
27 #include "avformat.h"
28 #include "internal.h"
29 #include "rtpdec.h"
30 #include "rtpdec_formats.h"
31
32 #define RTP_HEVC_PAYLOAD_HEADER_SIZE 2
33 #define RTP_HEVC_FU_HEADER_SIZE 1
34 #define RTP_HEVC_DONL_FIELD_SIZE 2
35 #define RTP_HEVC_DOND_FIELD_SIZE 1
36 #define RTP_HEVC_AP_NALU_LENGTH_FIELD_SIZE 2
37 #define HEVC_SPECIFIED_NAL_UNIT_TYPES 48
38
39 /* SDP out-of-band signaling data */
40 struct PayloadContext {
41 int using_donl_field;
42 int profile_id;
43 uint8_t *sps, *pps, *vps, *sei;
44 int sps_size, pps_size, vps_size, sei_size;
45 };
46
47 static const uint8_t start_sequence[] = { 0x00, 0x00, 0x00, 0x01 };
48
hevc_sdp_parse_fmtp_config(AVFormatContext * s,AVStream * stream,PayloadContext * hevc_data,const char * attr,const char * value)49 static av_cold int hevc_sdp_parse_fmtp_config(AVFormatContext *s,
50 AVStream *stream,
51 PayloadContext *hevc_data,
52 const char *attr, const char *value)
53 {
54 /* profile-space: 0-3 */
55 /* profile-id: 0-31 */
56 if (!strcmp(attr, "profile-id")) {
57 hevc_data->profile_id = atoi(value);
58 av_log(s, AV_LOG_TRACE, "SDP: found profile-id: %d\n", hevc_data->profile_id);
59 }
60
61 /* tier-flag: 0-1 */
62 /* level-id: 0-255 */
63 /* interop-constraints: [base16] */
64 /* profile-compatibility-indicator: [base16] */
65 /* sprop-sub-layer-id: 0-6, defines highest possible value for TID, default: 6 */
66 /* recv-sub-layer-id: 0-6 */
67 /* max-recv-level-id: 0-255 */
68 /* tx-mode: MSM,SSM */
69 /* sprop-vps: [base64] */
70 /* sprop-sps: [base64] */
71 /* sprop-pps: [base64] */
72 /* sprop-sei: [base64] */
73 if (!strcmp(attr, "sprop-vps") || !strcmp(attr, "sprop-sps") ||
74 !strcmp(attr, "sprop-pps") || !strcmp(attr, "sprop-sei")) {
75 uint8_t **data_ptr = NULL;
76 int *size_ptr = NULL;
77 if (!strcmp(attr, "sprop-vps")) {
78 data_ptr = &hevc_data->vps;
79 size_ptr = &hevc_data->vps_size;
80 } else if (!strcmp(attr, "sprop-sps")) {
81 data_ptr = &hevc_data->sps;
82 size_ptr = &hevc_data->sps_size;
83 } else if (!strcmp(attr, "sprop-pps")) {
84 data_ptr = &hevc_data->pps;
85 size_ptr = &hevc_data->pps_size;
86 } else if (!strcmp(attr, "sprop-sei")) {
87 data_ptr = &hevc_data->sei;
88 size_ptr = &hevc_data->sei_size;
89 } else
90 av_assert0(0);
91
92 ff_h264_parse_sprop_parameter_sets(s, data_ptr,
93 size_ptr, value);
94 }
95
96 /* max-lsr, max-lps, max-cpb, max-dpb, max-br, max-tr, max-tc */
97 /* max-fps */
98
99 /* sprop-max-don-diff: 0-32767
100
101 When the RTP stream depends on one or more other RTP
102 streams (in this case tx-mode MUST be equal to "MSM" and
103 MSM is in use), this parameter MUST be present and the
104 value MUST be greater than 0.
105 */
106 if (!strcmp(attr, "sprop-max-don-diff")) {
107 if (atoi(value) > 0)
108 hevc_data->using_donl_field = 1;
109 av_log(s, AV_LOG_TRACE, "Found sprop-max-don-diff in SDP, DON field usage is: %d\n",
110 hevc_data->using_donl_field);
111 }
112
113 /* sprop-depack-buf-nalus: 0-32767 */
114 if (!strcmp(attr, "sprop-depack-buf-nalus")) {
115 if (atoi(value) > 0)
116 hevc_data->using_donl_field = 1;
117 av_log(s, AV_LOG_TRACE, "Found sprop-depack-buf-nalus in SDP, DON field usage is: %d\n",
118 hevc_data->using_donl_field);
119 }
120
121 /* sprop-depack-buf-bytes: 0-4294967295 */
122 /* depack-buf-cap */
123 /* sprop-segmentation-id: 0-3 */
124 /* sprop-spatial-segmentation-idc: [base16] */
125 /* dec-parallel-ca: */
126 /* include-dph */
127
128 return 0;
129 }
130
hevc_parse_sdp_line(AVFormatContext * ctx,int st_index,PayloadContext * hevc_data,const char * line)131 static av_cold int hevc_parse_sdp_line(AVFormatContext *ctx, int st_index,
132 PayloadContext *hevc_data, const char *line)
133 {
134 AVStream *current_stream;
135 AVCodecParameters *par;
136 const char *sdp_line_ptr = line;
137
138 if (st_index < 0)
139 return 0;
140
141 current_stream = ctx->streams[st_index];
142 par = current_stream->codecpar;
143
144 if (av_strstart(sdp_line_ptr, "framesize:", &sdp_line_ptr)) {
145 ff_h264_parse_framesize(par, sdp_line_ptr);
146 } else if (av_strstart(sdp_line_ptr, "fmtp:", &sdp_line_ptr)) {
147 int ret = ff_parse_fmtp(ctx, current_stream, hevc_data, sdp_line_ptr,
148 hevc_sdp_parse_fmtp_config);
149 if (hevc_data->vps_size || hevc_data->sps_size ||
150 hevc_data->pps_size || hevc_data->sei_size) {
151 par->extradata_size = hevc_data->vps_size + hevc_data->sps_size +
152 hevc_data->pps_size + hevc_data->sei_size;
153 if ((ret = ff_alloc_extradata(par, par->extradata_size)) >= 0) {
154 int pos = 0;
155 memcpy(par->extradata + pos, hevc_data->vps, hevc_data->vps_size);
156 pos += hevc_data->vps_size;
157 memcpy(par->extradata + pos, hevc_data->sps, hevc_data->sps_size);
158 pos += hevc_data->sps_size;
159 memcpy(par->extradata + pos, hevc_data->pps, hevc_data->pps_size);
160 pos += hevc_data->pps_size;
161 memcpy(par->extradata + pos, hevc_data->sei, hevc_data->sei_size);
162 }
163
164 av_freep(&hevc_data->vps);
165 av_freep(&hevc_data->sps);
166 av_freep(&hevc_data->pps);
167 av_freep(&hevc_data->sei);
168 hevc_data->vps_size = 0;
169 hevc_data->sps_size = 0;
170 hevc_data->pps_size = 0;
171 hevc_data->sei_size = 0;
172 }
173 return ret;
174 }
175
176 return 0;
177 }
178
hevc_handle_packet(AVFormatContext * ctx,PayloadContext * rtp_hevc_ctx,AVStream * st,AVPacket * pkt,uint32_t * timestamp,const uint8_t * buf,int len,uint16_t seq,int flags)179 static int hevc_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_hevc_ctx,
180 AVStream *st, AVPacket *pkt, uint32_t *timestamp,
181 const uint8_t *buf, int len, uint16_t seq,
182 int flags)
183 {
184 const uint8_t *rtp_pl = buf;
185 int tid, lid, nal_type;
186 int first_fragment, last_fragment, fu_type;
187 uint8_t new_nal_header[2];
188 int res = 0;
189
190 /* sanity check for size of input packet: 1 byte payload at least */
191 if (len < RTP_HEVC_PAYLOAD_HEADER_SIZE + 1) {
192 av_log(ctx, AV_LOG_ERROR, "Too short RTP/HEVC packet, got %d bytes\n", len);
193 return AVERROR_INVALIDDATA;
194 }
195
196 /*
197 * decode the HEVC payload header according to section 4 of draft version 6:
198 *
199 * 0 1
200 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
201 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
202 * |F| Type | LayerId | TID |
203 * +-------------+-----------------+
204 *
205 * Forbidden zero (F): 1 bit
206 * NAL unit type (Type): 6 bits
207 * NUH layer ID (LayerId): 6 bits
208 * NUH temporal ID plus 1 (TID): 3 bits
209 */
210 nal_type = (buf[0] >> 1) & 0x3f;
211 lid = ((buf[0] << 5) & 0x20) | ((buf[1] >> 3) & 0x1f);
212 tid = buf[1] & 0x07;
213
214 /* sanity check for correct layer ID */
215 if (lid) {
216 /* future scalable or 3D video coding extensions */
217 avpriv_report_missing_feature(ctx, "Multi-layer HEVC coding");
218 return AVERROR_PATCHWELCOME;
219 }
220
221 /* sanity check for correct temporal ID */
222 if (!tid) {
223 av_log(ctx, AV_LOG_ERROR, "Illegal temporal ID in RTP/HEVC packet\n");
224 return AVERROR_INVALIDDATA;
225 }
226
227 /* sanity check for correct NAL unit type */
228 if (nal_type > 50) {
229 av_log(ctx, AV_LOG_ERROR, "Unsupported (HEVC) NAL type (%d)\n", nal_type);
230 return AVERROR_INVALIDDATA;
231 }
232
233 switch (nal_type) {
234 /* video parameter set (VPS) */
235 case 32:
236 /* sequence parameter set (SPS) */
237 case 33:
238 /* picture parameter set (PPS) */
239 case 34:
240 /* supplemental enhancement information (SEI) */
241 case 39:
242 /* single NAL unit packet */
243 default:
244 /* create A/V packet */
245 if ((res = av_new_packet(pkt, sizeof(start_sequence) + len)) < 0)
246 return res;
247 /* A/V packet: copy start sequence */
248 memcpy(pkt->data, start_sequence, sizeof(start_sequence));
249 /* A/V packet: copy NAL unit data */
250 memcpy(pkt->data + sizeof(start_sequence), buf, len);
251
252 break;
253 /* aggregated packet (AP) - with two or more NAL units */
254 case 48:
255 /* pass the HEVC payload header */
256 buf += RTP_HEVC_PAYLOAD_HEADER_SIZE;
257 len -= RTP_HEVC_PAYLOAD_HEADER_SIZE;
258
259 /* pass the HEVC DONL field */
260 if (rtp_hevc_ctx->using_donl_field) {
261 buf += RTP_HEVC_DONL_FIELD_SIZE;
262 len -= RTP_HEVC_DONL_FIELD_SIZE;
263 }
264
265 res = ff_h264_handle_aggregated_packet(ctx, rtp_hevc_ctx, pkt, buf, len,
266 rtp_hevc_ctx->using_donl_field ?
267 RTP_HEVC_DOND_FIELD_SIZE : 0,
268 NULL, 0);
269 if (res < 0)
270 return res;
271 break;
272 /* fragmentation unit (FU) */
273 case 49:
274 /* pass the HEVC payload header */
275 buf += RTP_HEVC_PAYLOAD_HEADER_SIZE;
276 len -= RTP_HEVC_PAYLOAD_HEADER_SIZE;
277
278 /*
279 * decode the FU header
280 *
281 * 0 1 2 3 4 5 6 7
282 * +-+-+-+-+-+-+-+-+
283 * |S|E| FuType |
284 * +---------------+
285 *
286 * Start fragment (S): 1 bit
287 * End fragment (E): 1 bit
288 * FuType: 6 bits
289 */
290 first_fragment = buf[0] & 0x80;
291 last_fragment = buf[0] & 0x40;
292 fu_type = buf[0] & 0x3f;
293
294 /* pass the HEVC FU header */
295 buf += RTP_HEVC_FU_HEADER_SIZE;
296 len -= RTP_HEVC_FU_HEADER_SIZE;
297
298 /* pass the HEVC DONL field */
299 if (rtp_hevc_ctx->using_donl_field) {
300 buf += RTP_HEVC_DONL_FIELD_SIZE;
301 len -= RTP_HEVC_DONL_FIELD_SIZE;
302 }
303
304 av_log(ctx, AV_LOG_TRACE, " FU type %d with %d bytes\n", fu_type, len);
305
306 /* sanity check for size of input packet: 1 byte payload at least */
307 if (len <= 0) {
308 if (len < 0) {
309 av_log(ctx, AV_LOG_ERROR,
310 "Too short RTP/HEVC packet, got %d bytes of NAL unit type %d\n",
311 len, nal_type);
312 return AVERROR_INVALIDDATA;
313 } else {
314 return AVERROR(EAGAIN);
315 }
316 }
317
318 if (first_fragment && last_fragment) {
319 av_log(ctx, AV_LOG_ERROR, "Illegal combination of S and E bit in RTP/HEVC packet\n");
320 return AVERROR_INVALIDDATA;
321 }
322
323 new_nal_header[0] = (rtp_pl[0] & 0x81) | (fu_type << 1);
324 new_nal_header[1] = rtp_pl[1];
325
326 res = ff_h264_handle_frag_packet(pkt, buf, len, first_fragment,
327 new_nal_header, sizeof(new_nal_header));
328
329 break;
330 /* PACI packet */
331 case 50:
332 /* Temporal scalability control information (TSCI) */
333 avpriv_report_missing_feature(ctx, "PACI packets for RTP/HEVC");
334 res = AVERROR_PATCHWELCOME;
335 break;
336 }
337
338 pkt->stream_index = st->index;
339
340 return res;
341 }
342
343 const RTPDynamicProtocolHandler ff_hevc_dynamic_handler = {
344 .enc_name = "H265",
345 .codec_type = AVMEDIA_TYPE_VIDEO,
346 .codec_id = AV_CODEC_ID_HEVC,
347 .need_parsing = AVSTREAM_PARSE_FULL,
348 .priv_data_size = sizeof(PayloadContext),
349 .parse_sdp_a_line = hevc_parse_sdp_line,
350 .parse_packet = hevc_handle_packet,
351 };
352