Rename rtpdec_theora.[ch] to rtpdec_xiph.[ch], as a preparation for merging
[libav.git] / libavformat / rtpdec_xiph.c
CommitLineData
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1/*
2 * RTP Theora Protocol
3 * Copyright (c) 2010 Josh Allmann
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/**
23 * @file libavformat/rtpdec_theora.c
24 * @brief Theora / RTP Code
25 * @author Josh Allmann <joshua.allmann@gmail.com>
26 */
27
28#include "libavutil/avstring.h"
29#include "libavutil/base64.h"
30#include "libavcodec/bytestream.h"
31
32#include <assert.h>
33
34#include "rtpdec.h"
06a36faf 35#include "rtpdec_xiph.h"
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36
37/**
38 * RTP/Theora specific private data.
39 */
40struct PayloadContext {
41 unsigned ident; ///< 24-bit stream configuration identifier
42 uint32_t timestamp;
43 ByteIOContext* fragment; ///< buffer for split payloads
44};
45
46static PayloadContext *theora_new_context(void)
47{
48 return av_mallocz(sizeof(PayloadContext));
49}
50
51static inline void free_fragment_if_needed(PayloadContext * data)
52{
53 if (data->fragment) {
54 uint8_t* p;
55 url_close_dyn_buf(data->fragment, &p);
56 av_free(p);
57 data->fragment = NULL;
58 }
59}
60
61static void theora_free_context(PayloadContext * data)
62{
63 free_fragment_if_needed(data);
64 av_free(data);
65}
66
67static int theora_handle_packet(AVFormatContext * ctx,
68 PayloadContext * data,
69 AVStream * st,
70 AVPacket * pkt,
71 uint32_t * timestamp,
72 const uint8_t * buf, int len, int flags)
73{
74
75 int ident, fragmented, tdt, num_pkts, pkt_len;
76
77 if (len < 6) {
78 av_log(ctx, AV_LOG_ERROR, "Invalid %d byte packet\n", len);
79 return AVERROR_INVALIDDATA;
80 }
81
82 // read theora rtp headers
83 ident = AV_RB24(buf);
84 fragmented = buf[3] >> 6;
85 tdt = (buf[3] >> 4) & 3;
86 num_pkts = buf[3] & 7;
87 pkt_len = AV_RB16(buf + 4);
88
89 if (pkt_len > len - 6) {
90 av_log(ctx, AV_LOG_ERROR,
91 "Invalid packet length %d in %d byte packet\n", pkt_len,
92 len);
93 return AVERROR_INVALIDDATA;
94 }
95
96 if (ident != data->ident) {
97 av_log(ctx, AV_LOG_ERROR,
98 "Unimplemented Theora SDP configuration change detected\n");
99 return AVERROR_PATCHWELCOME;
100 }
101
102 if (tdt) {
103 av_log(ctx, AV_LOG_ERROR,
104 "Unimplemented RTP Theora packet settings (%d,%d,%d)\n",
105 fragmented, tdt, num_pkts);
106 return AVERROR_PATCHWELCOME;
107 }
108
109 buf += 6; // move past header bits
110 len -= 6;
111
112 if (fragmented == 0) {
113 // whole frame(s)
114 int i, data_len, write_len;
115 buf -= 2;
116 len += 2;
117
118 // fast first pass to calculate total length
119 for (i = 0, data_len = 0; (i < num_pkts) && (len >= 2); i++) {
120 int off = data_len + (i << 1);
121 pkt_len = AV_RB16(buf + off);
122 data_len += pkt_len;
123 len -= pkt_len + 2;
124 }
125
126 if (len < 0 || i < num_pkts) {
127 av_log(ctx, AV_LOG_ERROR,
128 "Bad packet: %d bytes left at frame %d of %d\n",
129 len, i, num_pkts);
130 return AVERROR_INVALIDDATA;
131 }
132
133 if (av_new_packet(pkt, data_len)) {
134 av_log(ctx, AV_LOG_ERROR, "Out of memory.\n");
135 return AVERROR_NOMEM;
136 }
137 pkt->stream_index = st->index;
138
139 // concatenate frames
140 for (i = 0, write_len = 0; write_len < data_len; i++) {
141 pkt_len = AV_RB16(buf);
142 buf += 2;
143 memcpy(pkt->data + write_len, buf, pkt_len);
144 write_len += pkt_len;
145 buf += pkt_len;
146 }
147 assert(write_len == data_len);
148
149 return 0;
150
151 } else if (fragmented == 1) {
152 // start of theora data fragment
153 int res;
154
155 // end packet has been lost somewhere, so drop buffered data
156 free_fragment_if_needed(data);
157
158 if((res = url_open_dyn_buf(&data->fragment)) < 0)
159 return res;
160
161 put_buffer(data->fragment, buf, pkt_len);
162 data->timestamp = *timestamp;
163
164 } else {
165 assert(fragmented < 4);
166 if (data->timestamp != *timestamp) {
167 // skip if fragmented timestamp is incorrect;
168 // a start packet has been lost somewhere
169 free_fragment_if_needed(data);
170 av_log(ctx, AV_LOG_ERROR, "RTP timestamps don't match!\n");
171 return AVERROR_INVALIDDATA;
172 }
173
174 // copy data to fragment buffer
175 put_buffer(data->fragment, buf, pkt_len);
176
177 if (fragmented == 3) {
178 // end of theora data packet
179 uint8_t* theora_data;
180 int frame_size = url_close_dyn_buf(data->fragment, &theora_data);
181
182 if (frame_size < 0) {
183 av_log(ctx, AV_LOG_ERROR,
184 "Error occurred when getting fragment buffer.");
185 return frame_size;
186 }
187
188 if (av_new_packet(pkt, frame_size)) {
189 av_log(ctx, AV_LOG_ERROR, "Out of memory.\n");
190 return AVERROR_NOMEM;
191 }
192
193 memcpy(pkt->data, theora_data, frame_size);
194 pkt->stream_index = st->index;
195
196 av_free(theora_data);
197 data->fragment = NULL;
198
199 return 0;
200 }
201 }
202
203 return AVERROR(EAGAIN);
204}
205
206/**
207 * Length encoding described in RFC5215 section 3.1.1.
208 */
209static int get_base128(const uint8_t ** buf, const uint8_t * buf_end)
210{
211 int n = 0;
212 for (; *buf < buf_end; ++*buf) {
213 n <<= 7;
214 n += **buf & 0x7f;
215 if (!(**buf & 0x80)) {
216 ++*buf;
217 return n;
218 }
219 }
220 return 0;
221}
222
223/**
224 * Based off parse_packed_headers in Vorbis RTP
225 */
226static unsigned int
227parse_packed_headers(const uint8_t * packed_headers,
228 const uint8_t * packed_headers_end,
229 AVCodecContext * codec, PayloadContext * theora_data)
230{
231
232 unsigned num_packed, num_headers, length, length1, length2, extradata_alloc;
233 uint8_t *ptr;
234
235 if (packed_headers_end - packed_headers < 9) {
236 av_log(codec, AV_LOG_ERROR,
237 "Invalid %d byte packed header.",
238 packed_headers_end - packed_headers);
239 return AVERROR_INVALIDDATA;
240 }
241
242 num_packed = bytestream_get_be32(&packed_headers);
243 theora_data->ident = bytestream_get_be24(&packed_headers);
244 length = bytestream_get_be16(&packed_headers);
245 num_headers = get_base128(&packed_headers, packed_headers_end);
246 length1 = get_base128(&packed_headers, packed_headers_end);
247 length2 = get_base128(&packed_headers, packed_headers_end);
248
249 if (num_packed != 1 || num_headers > 3) {
250 av_log(codec, AV_LOG_ERROR,
251 "Unimplemented number of headers: %d packed headers, %d headers\n",
252 num_packed, num_headers);
253 return AVERROR_PATCHWELCOME;
254 }
255
256 if (packed_headers_end - packed_headers != length ||
257 length1 > length || length2 > length - length1) {
258 av_log(codec, AV_LOG_ERROR,
259 "Bad packed header lengths (%d,%d,%d,%d)\n", length1,
260 length2, packed_headers_end - packed_headers, length);
261 return AVERROR_INVALIDDATA;
262 }
263
264 /* allocate extra space:
265 * -- length/255 +2 for xiphlacing
266 * -- one for the '2' marker
267 * -- FF_INPUT_BUFFER_PADDING_SIZE required */
268 extradata_alloc = length + length/255 + 3 + FF_INPUT_BUFFER_PADDING_SIZE;
269
270 ptr = codec->extradata = av_malloc(extradata_alloc);
271 if (!ptr) {
272 av_log(codec, AV_LOG_ERROR, "Out of memory\n");
273 return AVERROR_NOMEM;
274 }
275 *ptr++ = 2;
276 ptr += av_xiphlacing(ptr, length1);
277 ptr += av_xiphlacing(ptr, length2);
278 memcpy(ptr, packed_headers, length);
279 ptr += length;
280 codec->extradata_size = ptr - codec->extradata;
281 // clear out remaining parts of the buffer
282 memset(ptr, 0, extradata_alloc - codec->extradata_size);
283
284 return 0;
285}
286
287static int theora_parse_fmtp_pair(AVCodecContext * codec,
288 PayloadContext *theora_data,
289 char *attr, char *value)
290{
291 int result = 0;
292
293 if (!strcmp(attr, "sampling")) {
294 return AVERROR_PATCHWELCOME;
295 } else if (!strcmp(attr, "width")) {
296 /* This is an integer between 1 and 1048561
297 * and MUST be in multiples of 16. */
298 codec->width = atoi(value);
299 return 0;
300 } else if (!strcmp(attr, "height")) {
301 /* This is an integer between 1 and 1048561
302 * and MUST be in multiples of 16. */
303 codec->height = atoi(value);
304 return 0;
305 } else if (!strcmp(attr, "delivery-method")) {
306 /* Possible values are: inline, in_band, out_band/specific_name. */
307 return AVERROR_PATCHWELCOME;
308 } else if (!strcmp(attr, "configuration-uri")) {
309 /* NOTE: configuration-uri is supported only under 2 conditions:
310 *--after the delivery-method tag
311 * --with a delivery-method value of out_band */
312 return AVERROR_PATCHWELCOME;
313 } else if (!strcmp(attr, "configuration")) {
314 /* NOTE: configuration is supported only AFTER the delivery-method tag
315 * The configuration value is a base64 encoded packed header */
316 uint8_t *decoded_packet = NULL;
317 int packet_size;
318 size_t decoded_alloc = strlen(value) / 4 * 3 + 4;
319
320 if (decoded_alloc <= INT_MAX) {
321 decoded_packet = av_malloc(decoded_alloc);
322 if (decoded_packet) {
323 packet_size =
324 av_base64_decode(decoded_packet, value, decoded_alloc);
325
326 result = parse_packed_headers
327 (decoded_packet, decoded_packet + packet_size, codec,
328 theora_data);
329 } else {
330 av_log(codec, AV_LOG_ERROR,
331 "Out of memory while decoding SDP configuration.\n");
332 result = AVERROR_NOMEM;
333 }
334 } else {
335 av_log(codec, AV_LOG_ERROR, "Packet too large\n");
336 result = AVERROR_INVALIDDATA;
337 }
338 av_free(decoded_packet);
339 }
340 return result;
341}
342
343static int theora_parse_sdp_line(AVFormatContext *s, int st_index,
344 PayloadContext *data, const char *line)
345{
346 const char *p;
347 char *value;
348 char attr[25];
349 int value_size = strlen(line), attr_size = sizeof(attr), res = 0;
350 AVCodecContext* codec = s->streams[st_index]->codec;
351
352 assert(codec->id == CODEC_ID_THEORA);
353 assert(data);
354
355 if (!(value = av_malloc(value_size))) {
356 av_log(codec, AV_LOG_ERROR, "Out of memory\n");
357 return AVERROR_NOMEM;
358 }
359
360 if (av_strstart(line, "fmtp:", &p)) {
361 // remove protocol identifier
362 while (*p && *p == ' ') p++; // strip spaces
363 while (*p && *p != ' ') p++; // eat protocol identifier
364 while (*p && *p == ' ') p++; // strip trailing spaces
365
366 while (ff_rtsp_next_attr_and_value(&p,
367 attr, attr_size,
368 value, value_size)) {
369 res = theora_parse_fmtp_pair(codec, data, attr, value);
370 if (res < 0 && res != AVERROR_PATCHWELCOME)
371 return res;
372 }
373 }
374
375 av_free(value);
376 return 0;
377}
378
379RTPDynamicProtocolHandler ff_theora_dynamic_handler = {
380 .enc_name = "theora",
72415b2a 381 .codec_type = AVMEDIA_TYPE_VIDEO,
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382 .codec_id = CODEC_ID_THEORA,
383 .parse_sdp_a_line = theora_parse_sdp_line,
384 .open = theora_new_context,
385 .close = theora_free_context,
386 .parse_packet = theora_handle_packet
387};