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rtpenc_jpeg.c
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1 /*
2  * RTP JPEG-compressed video Packetizer, RFC 2435
3  * Copyright (c) 2012 Samuel Pitoiset
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 "libavcodec/bytestream.h"
23 #include "libavcodec/mjpeg.h"
24 #include "libavcodec/jpegtables.h"
25 #include "libavutil/intreadwrite.h"
26 #include "rtpenc.h"
27 
29 {
30  RTPMuxContext *s = s1->priv_data;
31  const uint8_t *qtables[4] = { NULL };
32  int nb_qtables = 0;
33  uint8_t type;
34  uint8_t w, h;
35  uint8_t *p;
36  int off = 0; /* fragment offset of the current JPEG frame */
37  int len;
38  int i;
39  int default_huffman_tables = 0;
40 
41  s->buf_ptr = s->buf;
42  s->timestamp = s->cur_timestamp;
43 
44  /* convert video pixel dimensions from pixels to blocks */
45  w = AV_CEIL_RSHIFT(s1->streams[0]->codecpar->width, 3);
46  h = AV_CEIL_RSHIFT(s1->streams[0]->codecpar->height, 3);
47 
48  /* get the pixel format type or fail */
49  if (s1->streams[0]->codecpar->format == AV_PIX_FMT_YUVJ422P ||
52  type = 0;
53  } else if (s1->streams[0]->codecpar->format == AV_PIX_FMT_YUVJ420P ||
56  type = 1;
57  } else {
58  av_log(s1, AV_LOG_ERROR, "Unsupported pixel format\n");
59  return;
60  }
61 
62  /* preparse the header for getting some info */
63  for (i = 0; i < size; i++) {
64  if (buf[i] != 0xff)
65  continue;
66 
67  if (buf[i + 1] == DQT) {
68  int tables, j;
69  if (buf[i + 4] & 0xF0)
71  "Only 8-bit precision is supported.\n");
72 
73  /* a quantization table is 64 bytes long */
74  tables = AV_RB16(&buf[i + 2]) / 65;
75  if (i + 5 + tables * 65 > size) {
76  av_log(s1, AV_LOG_ERROR, "Too short JPEG header. Aborted!\n");
77  return;
78  }
79  if (nb_qtables + tables > 4) {
80  av_log(s1, AV_LOG_ERROR, "Invalid number of quantisation tables\n");
81  return;
82  }
83 
84  for (j = 0; j < tables; j++)
85  qtables[nb_qtables + j] = buf + i + 5 + j * 65;
86  nb_qtables += tables;
87  } else if (buf[i + 1] == SOF0) {
88  if (buf[i + 14] != 17 || buf[i + 17] != 17) {
89  av_log(s1, AV_LOG_ERROR,
90  "Only 1x1 chroma blocks are supported. Aborted!\n");
91  return;
92  }
93  } else if (buf[i + 1] == DHT) {
94  int dht_size = AV_RB16(&buf[i + 2]);
95  default_huffman_tables |= 1 << 4;
96  i += 3;
97  dht_size -= 2;
98  if (i + dht_size >= size)
99  continue;
100  while (dht_size > 0)
101  switch (buf[i + 1]) {
102  case 0x00:
103  if ( dht_size >= 29
104  && !memcmp(buf + i + 2, avpriv_mjpeg_bits_dc_luminance + 1, 16)
105  && !memcmp(buf + i + 18, avpriv_mjpeg_val_dc, 12)) {
106  default_huffman_tables |= 1;
107  i += 29;
108  dht_size -= 29;
109  } else {
110  i += dht_size;
111  dht_size = 0;
112  }
113  break;
114  case 0x01:
115  if ( dht_size >= 29
116  && !memcmp(buf + i + 2, avpriv_mjpeg_bits_dc_chrominance + 1, 16)
117  && !memcmp(buf + i + 18, avpriv_mjpeg_val_dc, 12)) {
118  default_huffman_tables |= 1 << 1;
119  i += 29;
120  dht_size -= 29;
121  } else {
122  i += dht_size;
123  dht_size = 0;
124  }
125  break;
126  case 0x10:
127  if ( dht_size >= 179
128  && !memcmp(buf + i + 2, avpriv_mjpeg_bits_ac_luminance + 1, 16)
129  && !memcmp(buf + i + 18, avpriv_mjpeg_val_ac_luminance, 162)) {
130  default_huffman_tables |= 1 << 2;
131  i += 179;
132  dht_size -= 179;
133  } else {
134  i += dht_size;
135  dht_size = 0;
136  }
137  break;
138  case 0x11:
139  if ( dht_size >= 179
140  && !memcmp(buf + i + 2, avpriv_mjpeg_bits_ac_chrominance + 1, 16)
141  && !memcmp(buf + i + 18, avpriv_mjpeg_val_ac_chrominance, 162)) {
142  default_huffman_tables |= 1 << 3;
143  i += 179;
144  dht_size -= 179;
145  } else {
146  i += dht_size;
147  dht_size = 0;
148  }
149  break;
150  default:
151  i += dht_size;
152  dht_size = 0;
153  continue;
154  }
155  } else if (buf[i + 1] == SOS) {
156  /* SOS is last marker in the header */
157  i += AV_RB16(&buf[i + 2]) + 2;
158  if (i > size) {
159  av_log(s1, AV_LOG_ERROR,
160  "Insufficient data. Aborted!\n");
161  return;
162  }
163  break;
164  }
165  }
166  if (default_huffman_tables && default_huffman_tables != 31) {
167  av_log(s1, AV_LOG_ERROR,
168  "RFC 2435 requires standard Huffman tables for jpeg\n");
169  return;
170  }
171  if (nb_qtables && nb_qtables != 2)
173  "RFC 2435 suggests two quantization tables, %d provided\n",
174  nb_qtables);
175 
176  /* skip JPEG header */
177  buf += i;
178  size -= i;
179 
180  for (i = size - 2; i >= 0; i--) {
181  if (buf[i] == 0xff && buf[i + 1] == EOI) {
182  /* Remove the EOI marker */
183  size = i;
184  break;
185  }
186  }
187 
188  p = s->buf_ptr;
189  while (size > 0) {
190  int hdr_size = 8;
191 
192  if (off == 0 && nb_qtables)
193  hdr_size += 4 + 64 * nb_qtables;
194 
195  /* payload max in one packet */
196  len = FFMIN(size, s->max_payload_size - hdr_size);
197 
198  /* set main header */
199  bytestream_put_byte(&p, 0);
200  bytestream_put_be24(&p, off);
201  bytestream_put_byte(&p, type);
202  bytestream_put_byte(&p, 255);
203  bytestream_put_byte(&p, w);
204  bytestream_put_byte(&p, h);
205 
206  if (off == 0 && nb_qtables) {
207  /* set quantization tables header */
208  bytestream_put_byte(&p, 0);
209  bytestream_put_byte(&p, 0);
210  bytestream_put_be16(&p, 64 * nb_qtables);
211 
212  for (i = 0; i < nb_qtables; i++)
213  bytestream_put_buffer(&p, qtables[i], 64);
214  }
215 
216  /* copy payload data */
217  memcpy(p, buf, len);
218 
219  /* marker bit is last packet in frame */
220  ff_rtp_send_data(s1, s->buf, len + hdr_size, size == len);
221 
222  buf += len;
223  size -= len;
224  off += len;
225  p = s->buf;
226  }
227 }
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
Definition: mjpeg.h:71
Definition: mjpeg.h:73
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int max_payload_size
Definition: rtpenc.h:38
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
MJPEG encoder and decoder.
Format I/O context.
Definition: avformat.h:1338
Definition: mjpeg.h:72
uint8_t
int width
Video only.
Definition: avcodec.h:4053
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1406
const uint8_t avpriv_mjpeg_bits_dc_luminance[17]
Definition: jpegtables.c:65
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting col...
Definition: pixfmt.h:75
uint8_t * buf
Definition: rtpenc.h:49
ptrdiff_t size
Definition: opengl_enc.c:101
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
const uint8_t avpriv_mjpeg_bits_dc_chrominance[17]
Definition: jpegtables.c:70
Definition: mjpeg.h:39
static const uint8_t *const tables[]
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:66
Definition: mjpeg.h:56
#define FFMIN(a, b)
Definition: common.h:96
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:74
void ff_rtp_send_data(AVFormatContext *s1, const uint8_t *buf1, int len, int m)
Definition: rtpenc.c:330
enum AVColorRange color_range
Video only.
Definition: avcodec.h:4073
the normal 2^n-1 "JPEG" YUV ranges
Definition: pixfmt.h:474
uint32_t cur_timestamp
Definition: rtpenc.h:37
void * buf
Definition: avisynth_c.h:690
GLint GLenum type
Definition: opengl_enc.c:105
const uint8_t avpriv_mjpeg_val_dc[12]
Definition: jpegtables.c:67
#define s1
Definition: regdef.h:38
const uint8_t avpriv_mjpeg_bits_ac_chrominance[17]
Definition: jpegtables.c:99
const uint8_t avpriv_mjpeg_val_ac_chrominance[]
Definition: jpegtables.c:102
uint8_t * buf_ptr
Definition: rtpenc.h:50
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:62
void ff_rtp_send_jpeg(AVFormatContext *s1, const uint8_t *buf, int size)
Definition: rtpenc_jpeg.c:28
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:368
const uint8_t avpriv_mjpeg_bits_ac_luminance[17]
Definition: jpegtables.c:73
uint32_t timestamp
Definition: rtpenc.h:35
int len
const uint8_t avpriv_mjpeg_val_ac_luminance[]
Definition: jpegtables.c:75
void * priv_data
Format private data.
Definition: avformat.h:1366
AVCodecParameters * codecpar
Definition: avformat.h:1241
#define AV_CEIL_RSHIFT(a, b)
Definition: common.h:58