Libav
rtpdec_jpeg.c
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1 /*
2  * RTP JPEG-compressed Video Depacketizer, RFC 2435
3  * Copyright (c) 2012 Samuel Pitoiset
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "avio_internal.h"
24 #include "rtpdec.h"
25 #include "rtpdec_formats.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavcodec/jpegtables.h"
28 #include "libavcodec/mjpeg.h"
29 #include "libavcodec/bytestream.h"
30 
34 struct PayloadContext {
36  uint32_t timestamp;
37  int hdr_size;
38  uint8_t qtables[128][128];
40 };
41 
42 static const uint8_t default_quantizers[128] = {
43  /* luma table */
44  16, 11, 12, 14, 12, 10, 16, 14,
45  13, 14, 18, 17, 16, 19, 24, 40,
46  26, 24, 22, 22, 24, 49, 35, 37,
47  29, 40, 58, 51, 61, 60, 57, 51,
48  56, 55, 64, 72, 92, 78, 64, 68,
49  87, 69, 55, 56, 80, 109, 81, 87,
50  95, 98, 103, 104, 103, 62, 77, 113,
51  121, 112, 100, 120, 92, 101, 103, 99,
52 
53  /* chroma table */
54  17, 18, 18, 24, 21, 24, 47, 26,
55  26, 47, 99, 66, 56, 66, 99, 99,
56  99, 99, 99, 99, 99, 99, 99, 99,
57  99, 99, 99, 99, 99, 99, 99, 99,
58  99, 99, 99, 99, 99, 99, 99, 99,
59  99, 99, 99, 99, 99, 99, 99, 99,
60  99, 99, 99, 99, 99, 99, 99, 99,
61  99, 99, 99, 99, 99, 99, 99, 99
62 };
63 
65 {
66  ffio_free_dyn_buf(&jpeg->frame);
67 }
68 
69 static int jpeg_create_huffman_table(PutByteContext *p, int table_class,
70  int table_id, const uint8_t *bits_table,
71  const uint8_t *value_table)
72 {
73  int i, n = 0;
74 
75  bytestream2_put_byte(p, table_class << 4 | table_id);
76 
77  for (i = 1; i <= 16; i++) {
78  n += bits_table[i];
79  bytestream2_put_byte(p, bits_table[i]);
80  }
81 
82  for (i = 0; i < n; i++) {
83  bytestream2_put_byte(p, value_table[i]);
84  }
85  return n + 17;
86 }
87 
88 static void jpeg_put_marker(PutByteContext *pbc, int code)
89 {
90  bytestream2_put_byte(pbc, 0xff);
91  bytestream2_put_byte(pbc, code);
92 }
93 
94 static int jpeg_create_header(uint8_t *buf, int size, uint32_t type, uint32_t w,
95  uint32_t h, const uint8_t *qtable, int nb_qtable)
96 {
97  PutByteContext pbc;
98  uint8_t *dht_size_ptr;
99  int dht_size, i;
100 
101  bytestream2_init_writer(&pbc, buf, size);
102 
103  /* Convert from blocks to pixels. */
104  w <<= 3;
105  h <<= 3;
106 
107  /* SOI */
108  jpeg_put_marker(&pbc, SOI);
109 
110  /* JFIF header */
111  jpeg_put_marker(&pbc, APP0);
112  bytestream2_put_be16(&pbc, 16);
113  bytestream2_put_buffer(&pbc, "JFIF", 5);
114  bytestream2_put_be16(&pbc, 0x0201);
115  bytestream2_put_byte(&pbc, 0);
116  bytestream2_put_be16(&pbc, 1);
117  bytestream2_put_be16(&pbc, 1);
118  bytestream2_put_byte(&pbc, 0);
119  bytestream2_put_byte(&pbc, 0);
120 
121  /* DQT */
122  jpeg_put_marker(&pbc, DQT);
123  bytestream2_put_be16(&pbc, 2 + nb_qtable * (1 + 64));
124 
125  for (i = 0; i < nb_qtable; i++) {
126  bytestream2_put_byte(&pbc, i);
127 
128  /* Each table is an array of 64 values given in zig-zag
129  * order, identical to the format used in a JFIF DQT
130  * marker segment. */
131  bytestream2_put_buffer(&pbc, qtable + 64 * i, 64);
132  }
133 
134  /* DHT */
135  jpeg_put_marker(&pbc, DHT);
136  dht_size_ptr = pbc.buffer;
137  bytestream2_put_be16(&pbc, 0);
138 
139  dht_size = 2;
148  AV_WB16(dht_size_ptr, dht_size);
149 
150  /* SOF0 */
151  jpeg_put_marker(&pbc, SOF0);
152  bytestream2_put_be16(&pbc, 17); /* size */
153  bytestream2_put_byte(&pbc, 8); /* bits per component */
154  bytestream2_put_be16(&pbc, h);
155  bytestream2_put_be16(&pbc, w);
156  bytestream2_put_byte(&pbc, 3); /* number of components */
157  bytestream2_put_byte(&pbc, 1); /* component number */
158  bytestream2_put_byte(&pbc, (2 << 4) | (type ? 2 : 1)); /* hsample/vsample */
159  bytestream2_put_byte(&pbc, 0); /* matrix number */
160  bytestream2_put_byte(&pbc, 2); /* component number */
161  bytestream2_put_byte(&pbc, 1 << 4 | 1); /* hsample/vsample */
162  bytestream2_put_byte(&pbc, nb_qtable == 2 ? 1 : 0); /* matrix number */
163  bytestream2_put_byte(&pbc, 3); /* component number */
164  bytestream2_put_byte(&pbc, 1 << 4 | 1); /* hsample/vsample */
165  bytestream2_put_byte(&pbc, nb_qtable == 2 ? 1 : 0); /* matrix number */
166 
167  /* SOS */
168  jpeg_put_marker(&pbc, SOS);
169  bytestream2_put_be16(&pbc, 12);
170  bytestream2_put_byte(&pbc, 3);
171  bytestream2_put_byte(&pbc, 1);
172  bytestream2_put_byte(&pbc, 0);
173  bytestream2_put_byte(&pbc, 2);
174  bytestream2_put_byte(&pbc, 17);
175  bytestream2_put_byte(&pbc, 3);
176  bytestream2_put_byte(&pbc, 17);
177  bytestream2_put_byte(&pbc, 0);
178  bytestream2_put_byte(&pbc, 63);
179  bytestream2_put_byte(&pbc, 0);
180 
181  /* Return the length in bytes of the JPEG header. */
182  return bytestream2_tell_p(&pbc);
183 }
184 
186 {
187  int factor = q;
188  int i;
189  uint16_t S;
190 
191  factor = av_clip(q, 1, 99);
192 
193  if (q < 50)
194  S = 5000 / factor;
195  else
196  S = 200 - factor * 2;
197 
198  for (i = 0; i < 128; i++) {
199  int val = (default_quantizers[i] * S + 50) / 100;
200 
201  /* Limit the quantizers to 1 <= q <= 255. */
202  val = av_clip(val, 1, 255);
203  qtables[i] = val;
204  }
205 }
206 
208  AVStream *st, AVPacket *pkt, uint32_t *timestamp,
209  const uint8_t *buf, int len, uint16_t seq,
210  int flags)
211 {
212  uint8_t type, q, width, height;
213  const uint8_t *qtables = NULL;
214  uint16_t qtable_len;
215  uint32_t off;
216  int ret;
217 
218  if (len < 8) {
219  av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
220  return AVERROR_INVALIDDATA;
221  }
222 
223  /* Parse the main JPEG header. */
224  off = AV_RB24(buf + 1); /* fragment byte offset */
225  type = AV_RB8(buf + 4); /* id of jpeg decoder params */
226  q = AV_RB8(buf + 5); /* quantization factor (or table id) */
227  width = AV_RB8(buf + 6); /* frame width in 8 pixel blocks */
228  height = AV_RB8(buf + 7); /* frame height in 8 pixel blocks */
229  buf += 8;
230  len -= 8;
231 
232  if (type > 1) {
233  av_log(ctx, AV_LOG_ERROR, "Unimplemented RTP/JPEG type %d\n", type);
234  return AVERROR_PATCHWELCOME;
235  }
236 
237  /* Parse the quantization table header. */
238  if (off == 0) {
239  /* Start of JPEG data packet. */
240  uint8_t new_qtables[128];
241  uint8_t hdr[1024];
242 
243  if (q > 127) {
244  uint8_t precision;
245  if (len < 4) {
246  av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
247  return AVERROR_INVALIDDATA;
248  }
249 
250  /* The first byte is reserved for future use. */
251  precision = AV_RB8(buf + 1); /* size of coefficients */
252  qtable_len = AV_RB16(buf + 2); /* length in bytes */
253  buf += 4;
254  len -= 4;
255 
256  if (precision)
257  av_log(ctx, AV_LOG_WARNING, "Only 8-bit precision is supported.\n");
258 
259  if (qtable_len > 0) {
260  if (len < qtable_len) {
261  av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
262  return AVERROR_INVALIDDATA;
263  }
264  qtables = buf;
265  buf += qtable_len;
266  len -= qtable_len;
267  if (q < 255) {
268  if (jpeg->qtables_len[q - 128] &&
269  (jpeg->qtables_len[q - 128] != qtable_len ||
270  memcmp(qtables, &jpeg->qtables[q - 128][0], qtable_len))) {
271  av_log(ctx, AV_LOG_WARNING,
272  "Quantization tables for q=%d changed\n", q);
273  } else if (!jpeg->qtables_len[q - 128] && qtable_len <= 128) {
274  memcpy(&jpeg->qtables[q - 128][0], qtables,
275  qtable_len);
276  jpeg->qtables_len[q - 128] = qtable_len;
277  }
278  }
279  } else {
280  if (q == 255) {
281  av_log(ctx, AV_LOG_ERROR,
282  "Invalid RTP/JPEG packet. Quantization tables not found.\n");
283  return AVERROR_INVALIDDATA;
284  }
285  if (!jpeg->qtables_len[q - 128]) {
286  av_log(ctx, AV_LOG_ERROR,
287  "No quantization tables known for q=%d yet.\n", q);
288  return AVERROR_INVALIDDATA;
289  }
290  qtables = &jpeg->qtables[q - 128][0];
291  qtable_len = jpeg->qtables_len[q - 128];
292  }
293  } else { /* q <= 127 */
294  if (q == 0 || q > 99) {
295  av_log(ctx, AV_LOG_ERROR, "Reserved q value %d\n", q);
296  return AVERROR_INVALIDDATA;
297  }
298  create_default_qtables(new_qtables, q);
299  qtables = new_qtables;
300  qtable_len = sizeof(new_qtables);
301  }
302 
303  /* Skip the current frame in case of the end packet
304  * has been lost somewhere. */
305  ffio_free_dyn_buf(&jpeg->frame);
306 
307  if ((ret = avio_open_dyn_buf(&jpeg->frame)) < 0)
308  return ret;
309  jpeg->timestamp = *timestamp;
310 
311  /* Generate a frame and scan headers that can be prepended to the
312  * RTP/JPEG data payload to produce a JPEG compressed image in
313  * interchange format. */
314  jpeg->hdr_size = jpeg_create_header(hdr, sizeof(hdr), type, width,
315  height, qtables,
316  qtable_len / 64);
317 
318  /* Copy JPEG header to frame buffer. */
319  avio_write(jpeg->frame, hdr, jpeg->hdr_size);
320  }
321 
322  if (!jpeg->frame) {
323  av_log(ctx, AV_LOG_ERROR,
324  "Received packet without a start chunk; dropping frame.\n");
325  return AVERROR(EAGAIN);
326  }
327 
328  if (jpeg->timestamp != *timestamp) {
329  /* Skip the current frame if timestamp is incorrect.
330  * A start packet has been lost somewhere. */
331  ffio_free_dyn_buf(&jpeg->frame);
332  av_log(ctx, AV_LOG_ERROR, "RTP timestamps don't match.\n");
333  return AVERROR_INVALIDDATA;
334  }
335 
336  if (off != avio_tell(jpeg->frame) - jpeg->hdr_size) {
337  av_log(ctx, AV_LOG_ERROR,
338  "Missing packets; dropping frame.\n");
339  return AVERROR(EAGAIN);
340  }
341 
342  /* Copy data to frame buffer. */
343  avio_write(jpeg->frame, buf, len);
344 
345  if (flags & RTP_FLAG_MARKER) {
346  /* End of JPEG data packet. */
347  uint8_t buf[2] = { 0xff, EOI };
348 
349  /* Put EOI marker. */
350  avio_write(jpeg->frame, buf, sizeof(buf));
351 
352  /* Prepare the JPEG packet. */
353  if ((ret = ff_rtp_finalize_packet(pkt, &jpeg->frame, st->index)) < 0) {
354  av_log(ctx, AV_LOG_ERROR,
355  "Error occurred when getting frame buffer.\n");
356  return ret;
357  }
358 
359  return 0;
360  }
361 
362  return AVERROR(EAGAIN);
363 }
364 
366  .enc_name = "JPEG",
367  .codec_type = AVMEDIA_TYPE_VIDEO,
368  .codec_id = AV_CODEC_ID_MJPEG,
369  .priv_data_size = sizeof(PayloadContext),
370  .close = jpeg_close_context,
372  .static_payload_id = 26,
373 };
AVPacket pkt
Definition: rtpdec_qt.c:37
#define AV_RB8(x)
Definition: intreadwrite.h:368
Bytestream IO Context.
Definition: avio.h:104
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
int size
Definition: mjpeg.h:71
Definition: mjpeg.h:73
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:130
RTP/JPEG specific private data.
Definition: rdt.c:83
int index
stream index in AVFormatContext
Definition: avformat.h:706
static av_always_inline void bytestream2_init_writer(PutByteContext *p, uint8_t *buf, int buf_size)
Definition: bytestream.h:141
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
#define AV_RB24
Definition: intreadwrite.h:64
MJPEG encoder and decoder.
int avio_open_dyn_buf(AVIOContext **s)
Open a write only memory stream.
Definition: aviobuf.c:1143
AVIOContext * frame
current frame buffer
Definition: rtpdec_jpeg.c:35
Format I/O context.
Definition: avformat.h:940
Definition: mjpeg.h:72
uint8_t
static int jpeg_create_huffman_table(PutByteContext *p, int table_class, int table_id, const uint8_t *bits_table, const uint8_t *value_table)
Definition: rtpdec_jpeg.c:69
static void jpeg_put_marker(PutByteContext *pbc, int code)
Definition: rtpdec_jpeg.c:88
const uint8_t avpriv_mjpeg_bits_dc_luminance[17]
Definition: jpegtables.c:65
static int flags
Definition: log.c:50
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:295
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:221
RTPDynamicProtocolHandler ff_jpeg_dynamic_handler
Definition: rtpdec_jpeg.c:365
uint32_t timestamp
current frame timestamp
Definition: rtpdec_ac3.c:31
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
#define RTP_FLAG_MARKER
RTP marker bit was set for this packet.
Definition: rtpdec.h:93
#define S(s, c, i)
#define AV_RB16
Definition: intreadwrite.h:53
#define AVERROR(e)
Definition: error.h:43
uint8_t qtables[128][128]
Definition: rtpdec_jpeg.c:38
const uint8_t avpriv_mjpeg_bits_dc_chrominance[17]
Definition: jpegtables.c:70
static void jpeg_close_context(PayloadContext *jpeg)
Definition: rtpdec_jpeg.c:64
static av_always_inline int bytestream2_tell_p(PutByteContext *p)
Definition: bytestream.h:190
Definition: mjpeg.h:39
Definition: mjpeg.h:70
Definition: mjpeg.h:79
Definition: mjpeg.h:56
AVFormatContext * ctx
Definition: movenc.c:48
static av_always_inline unsigned int bytestream2_put_buffer(PutByteContext *p, const uint8_t *src, unsigned int size)
Definition: bytestream.h:279
static void create_default_qtables(uint8_t *qtables, uint8_t q)
Definition: rtpdec_jpeg.c:185
void ffio_free_dyn_buf(AVIOContext **s)
Free a dynamic buffer.
Definition: aviobuf.c:1183
static int jpeg_parse_packet(AVFormatContext *ctx, PayloadContext *jpeg, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Definition: rtpdec_jpeg.c:207
Stream structure.
Definition: avformat.h:705
#define AVERROR_PATCHWELCOME
Not yet implemented in Libav, patches welcome.
Definition: error.h:57
NULL
Definition: eval.c:55
uint8_t * buffer
Definition: bytestream.h:37
static int width
Definition: utils.c:156
const uint8_t avpriv_mjpeg_val_dc[12]
Definition: jpegtables.c:67
uint8_t qtables_len[128]
Definition: rtpdec_jpeg.c:39
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:168
const uint8_t avpriv_mjpeg_bits_ac_chrominance[17]
Definition: jpegtables.c:99
const char * enc_name
Definition: rtpdec.h:116
const uint8_t avpriv_mjpeg_val_ac_chrominance[]
Definition: jpegtables.c:102
static int jpeg_create_header(uint8_t *buf, int size, uint32_t type, uint32_t w, uint32_t h, const uint8_t *qtable, int nb_qtable)
Definition: rtpdec_jpeg.c:94
int height
Definition: gxfenc.c:72
Main libavformat public API header.
static const uint8_t default_quantizers[128]
Definition: rtpdec_jpeg.c:42
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:891
const uint8_t avpriv_mjpeg_bits_ac_luminance[17]
Definition: jpegtables.c:73
static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index)
Parse a packet, add all split parts to parse_queue.
Definition: utils.c:816
const uint8_t avpriv_mjpeg_val_ac_luminance[]
Definition: jpegtables.c:75
int hdr_size
size of the current frame header
Definition: rtpdec_jpeg.c:37
#define AV_WB16(p, val)
Definition: intreadwrite.h:218
This structure stores compressed data.
Definition: avcodec.h:1323