Libav
libtheoraenc.c
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1 /*
2  * Copyright (c) 2006 Paul Richards <paul.richards@gmail.com>
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
33 /* Libav includes */
34 #include "libavutil/common.h"
35 #include "libavutil/intreadwrite.h"
36 #include "libavutil/pixdesc.h"
37 #include "libavutil/log.h"
38 #include "libavutil/base64.h"
39 #include "avcodec.h"
40 #include "internal.h"
41 
42 /* libtheora includes */
43 #include <theora/theoraenc.h>
44 
45 typedef struct TheoraContext {
46  th_enc_ctx *t_state;
50  int uv_hshift;
51  int uv_vshift;
54 
56 static int concatenate_packet(unsigned int* offset,
57  AVCodecContext* avc_context,
58  const ogg_packet* packet)
59 {
60  const char* message = NULL;
61  int newsize = avc_context->extradata_size + 2 + packet->bytes;
62  int err = AVERROR_INVALIDDATA;
63 
64  if (packet->bytes < 0) {
65  message = "ogg_packet has negative size";
66  } else if (packet->bytes > 0xffff) {
67  message = "ogg_packet is larger than 65535 bytes";
68  } else if (newsize < avc_context->extradata_size) {
69  message = "extradata_size would overflow";
70  } else {
71  if ((err = av_reallocp(&avc_context->extradata, newsize)) < 0) {
72  avc_context->extradata_size = 0;
73  message = "av_realloc failed";
74  }
75  }
76  if (message) {
77  av_log(avc_context, AV_LOG_ERROR, "concatenate_packet failed: %s\n", message);
78  return err;
79  }
80 
81  avc_context->extradata_size = newsize;
82  AV_WB16(avc_context->extradata + (*offset), packet->bytes);
83  *offset += 2;
84  memcpy(avc_context->extradata + (*offset), packet->packet, packet->bytes);
85  (*offset) += packet->bytes;
86  return 0;
87 }
88 
89 static int get_stats(AVCodecContext *avctx, int eos)
90 {
91 #ifdef TH_ENCCTL_2PASS_OUT
92  TheoraContext *h = avctx->priv_data;
93  uint8_t *buf;
94  int bytes;
95 
96  bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_OUT, &buf, sizeof(buf));
97  if (bytes < 0) {
98  av_log(avctx, AV_LOG_ERROR, "Error getting first pass stats\n");
99  return -1;
100  }
101  if (!eos) {
102  h->stats = av_fast_realloc(h->stats, &h->stats_size,
103  h->stats_offset + bytes);
104  memcpy(h->stats + h->stats_offset, buf, bytes);
105  h->stats_offset += bytes;
106  } else {
107  int b64_size = AV_BASE64_SIZE(h->stats_offset);
108  // libtheora generates a summary header at the end
109  memcpy(h->stats, buf, bytes);
110  avctx->stats_out = av_malloc(b64_size);
111  av_base64_encode(avctx->stats_out, b64_size, h->stats, h->stats_offset);
112  }
113  return 0;
114 #else
115  av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
116  return -1;
117 #endif
118 }
119 
120 // libtheora won't read the entire buffer we give it at once, so we have to
121 // repeatedly submit it...
122 static int submit_stats(AVCodecContext *avctx)
123 {
124 #ifdef TH_ENCCTL_2PASS_IN
125  TheoraContext *h = avctx->priv_data;
126  int bytes;
127  if (!h->stats) {
128  if (!avctx->stats_in) {
129  av_log(avctx, AV_LOG_ERROR, "No statsfile for second pass\n");
130  return -1;
131  }
132  h->stats_size = strlen(avctx->stats_in) * 3/4;
133  h->stats = av_malloc(h->stats_size);
134  h->stats_size = av_base64_decode(h->stats, avctx->stats_in, h->stats_size);
135  }
136  while (h->stats_size - h->stats_offset > 0) {
137  bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_IN,
138  h->stats + h->stats_offset,
139  h->stats_size - h->stats_offset);
140  if (bytes < 0) {
141  av_log(avctx, AV_LOG_ERROR, "Error submitting stats\n");
142  return -1;
143  }
144  if (!bytes)
145  return 0;
146  h->stats_offset += bytes;
147  }
148  return 0;
149 #else
150  av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
151  return -1;
152 #endif
153 }
154 
155 static av_cold int encode_init(AVCodecContext* avc_context)
156 {
157  th_info t_info;
158  th_comment t_comment;
159  ogg_packet o_packet;
160  unsigned int offset;
161  TheoraContext *h = avc_context->priv_data;
162  uint32_t gop_size = avc_context->gop_size;
163 
164  /* Set up the theora_info struct */
165  th_info_init(&t_info);
166  t_info.frame_width = FFALIGN(avc_context->width, 16);
167  t_info.frame_height = FFALIGN(avc_context->height, 16);
168  t_info.pic_width = avc_context->width;
169  t_info.pic_height = avc_context->height;
170  t_info.pic_x = 0;
171  t_info.pic_y = 0;
172  /* Swap numerator and denominator as time_base in AVCodecContext gives the
173  * time period between frames, but theora_info needs the framerate. */
174  t_info.fps_numerator = avc_context->time_base.den;
175  t_info.fps_denominator = avc_context->time_base.num;
176  if (avc_context->sample_aspect_ratio.num) {
177  t_info.aspect_numerator = avc_context->sample_aspect_ratio.num;
178  t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
179  } else {
180  t_info.aspect_numerator = 1;
181  t_info.aspect_denominator = 1;
182  }
183 
184  if (avc_context->color_primaries == AVCOL_PRI_BT470M)
185  t_info.colorspace = TH_CS_ITU_REC_470M;
186  else if (avc_context->color_primaries == AVCOL_PRI_BT470BG)
187  t_info.colorspace = TH_CS_ITU_REC_470BG;
188  else
189  t_info.colorspace = TH_CS_UNSPECIFIED;
190 
191  if (avc_context->pix_fmt == AV_PIX_FMT_YUV420P)
192  t_info.pixel_fmt = TH_PF_420;
193  else if (avc_context->pix_fmt == AV_PIX_FMT_YUV422P)
194  t_info.pixel_fmt = TH_PF_422;
195  else if (avc_context->pix_fmt == AV_PIX_FMT_YUV444P)
196  t_info.pixel_fmt = TH_PF_444;
197  else {
198  av_log(avc_context, AV_LOG_ERROR, "Unsupported pix_fmt\n");
199  return -1;
200  }
202  &h->uv_hshift, &h->uv_vshift);
203 
204  if (avc_context->flags & CODEC_FLAG_QSCALE) {
205  /* to be constant with the libvorbis implementation, clip global_quality to 0 - 10
206  Theora accepts a quality parameter p, which is:
207  * 0 <= p <=63
208  * an int value
209  */
210  t_info.quality = av_clipf(avc_context->global_quality / (float)FF_QP2LAMBDA, 0, 10) * 6.3;
211  t_info.target_bitrate = 0;
212  } else {
213  t_info.target_bitrate = avc_context->bit_rate;
214  t_info.quality = 0;
215  }
216 
217  /* Now initialise libtheora */
218  h->t_state = th_encode_alloc(&t_info);
219  if (!h->t_state) {
220  av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
221  return -1;
222  }
223 
224  h->keyframe_mask = (1 << t_info.keyframe_granule_shift) - 1;
225  /* Clear up theora_info struct */
226  th_info_clear(&t_info);
227 
228  if (th_encode_ctl(h->t_state, TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
229  &gop_size, sizeof(gop_size))) {
230  av_log(avc_context, AV_LOG_ERROR, "Error setting GOP size\n");
231  return -1;
232  }
233 
234  // need to enable 2 pass (via TH_ENCCTL_2PASS_) before encoding headers
235  if (avc_context->flags & CODEC_FLAG_PASS1) {
236  if (get_stats(avc_context, 0))
237  return -1;
238  } else if (avc_context->flags & CODEC_FLAG_PASS2) {
239  if (submit_stats(avc_context))
240  return -1;
241  }
242 
243  /*
244  Output first header packet consisting of theora
245  header, comment, and tables.
246 
247  Each one is prefixed with a 16bit size, then they
248  are concatenated together into libavcodec's extradata.
249  */
250  offset = 0;
251 
252  /* Headers */
253  th_comment_init(&t_comment);
254 
255  while (th_encode_flushheader(h->t_state, &t_comment, &o_packet))
256  if (concatenate_packet(&offset, avc_context, &o_packet))
257  return -1;
258 
259  th_comment_clear(&t_comment);
260 
261  /* Set up the output AVFrame */
262  avc_context->coded_frame = av_frame_alloc();
263 
264  return 0;
265 }
266 
267 static int encode_frame(AVCodecContext* avc_context, AVPacket *pkt,
268  const AVFrame *frame, int *got_packet)
269 {
270  th_ycbcr_buffer t_yuv_buffer;
271  TheoraContext *h = avc_context->priv_data;
272  ogg_packet o_packet;
273  int result, i, ret;
274 
275  // EOS, finish and get 1st pass stats if applicable
276  if (!frame) {
277  th_encode_packetout(h->t_state, 1, &o_packet);
278  if (avc_context->flags & CODEC_FLAG_PASS1)
279  if (get_stats(avc_context, 1))
280  return -1;
281  return 0;
282  }
283 
284  /* Copy planes to the theora yuv_buffer */
285  for (i = 0; i < 3; i++) {
286  t_yuv_buffer[i].width = FFALIGN(avc_context->width, 16) >> (i && h->uv_hshift);
287  t_yuv_buffer[i].height = FFALIGN(avc_context->height, 16) >> (i && h->uv_vshift);
288  t_yuv_buffer[i].stride = frame->linesize[i];
289  t_yuv_buffer[i].data = frame->data[i];
290  }
291 
292  if (avc_context->flags & CODEC_FLAG_PASS2)
293  if (submit_stats(avc_context))
294  return -1;
295 
296  /* Now call into theora_encode_YUVin */
297  result = th_encode_ycbcr_in(h->t_state, t_yuv_buffer);
298  if (result) {
299  const char* message;
300  switch (result) {
301  case -1:
302  message = "differing frame sizes";
303  break;
304  case TH_EINVAL:
305  message = "encoder is not ready or is finished";
306  break;
307  default:
308  message = "unknown reason";
309  break;
310  }
311  av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
312  return -1;
313  }
314 
315  if (avc_context->flags & CODEC_FLAG_PASS1)
316  if (get_stats(avc_context, 0))
317  return -1;
318 
319  /* Pick up returned ogg_packet */
320  result = th_encode_packetout(h->t_state, 0, &o_packet);
321  switch (result) {
322  case 0:
323  /* No packet is ready */
324  return 0;
325  case 1:
326  /* Success, we have a packet */
327  break;
328  default:
329  av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
330  return -1;
331  }
332 
333  /* Copy ogg_packet content out to buffer */
334  if ((ret = ff_alloc_packet(pkt, o_packet.bytes)) < 0) {
335  av_log(avc_context, AV_LOG_ERROR, "Error getting output packet of size %ld.\n", o_packet.bytes);
336  return ret;
337  }
338  memcpy(pkt->data, o_packet.packet, o_packet.bytes);
339 
340  // HACK: assumes no encoder delay, this is true until libtheora becomes
341  // multithreaded (which will be disabled unless explicitly requested)
342  pkt->pts = pkt->dts = frame->pts;
343  avc_context->coded_frame->key_frame = !(o_packet.granulepos & h->keyframe_mask);
344  if (avc_context->coded_frame->key_frame)
345  pkt->flags |= AV_PKT_FLAG_KEY;
346  *got_packet = 1;
347 
348  return 0;
349 }
350 
351 static av_cold int encode_close(AVCodecContext* avc_context)
352 {
353  TheoraContext *h = avc_context->priv_data;
354 
355  th_encode_free(h->t_state);
356  av_freep(&h->stats);
357  av_freep(&avc_context->coded_frame);
358  av_freep(&avc_context->stats_out);
359  av_freep(&avc_context->extradata);
360  avc_context->extradata_size = 0;
361 
362  return 0;
363 }
364 
367  .name = "libtheora",
368  .long_name = NULL_IF_CONFIG_SMALL("libtheora Theora"),
369  .type = AVMEDIA_TYPE_VIDEO,
370  .id = AV_CODEC_ID_THEORA,
371  .priv_data_size = sizeof(TheoraContext),
372  .init = encode_init,
373  .close = encode_close,
374  .encode2 = encode_frame,
375  .capabilities = CODEC_CAP_DELAY, // needed to get the statsfile summary
376  .pix_fmts = (const enum AVPixelFormat[]){
378  },
379 };
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
uint8_t * stats
Definition: libtheoraenc.c:47
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
#define CODEC_FLAG_PASS2
Use internal 2pass ratecontrol in second pass mode.
Definition: avcodec.h:636
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:70
#define CODEC_FLAG_PASS1
Use internal 2pass ratecontrol in first pass mode.
Definition: avcodec.h:635
AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:2548
static int concatenate_packet(unsigned int *offset, AVCodecContext *avc_context, const ogg_packet *packet)
Concatenate an ogg_packet into the extradata.
Definition: libtheoraenc.c:56
int num
numerator
Definition: rational.h:44
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel...
Definition: avcodec.h:1445
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1270
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:2316
AVCodec.
Definition: avcodec.h:2812
#define FFALIGN(x, a)
Definition: common.h:62
static int submit_stats(AVCodecContext *avctx)
Definition: libtheoraenc.c:122
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1175
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
uint8_t
#define av_cold
Definition: attributes.h:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:211
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1164
uint8_t * data
Definition: avcodec.h:973
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:140
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:2308
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1019
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
void * av_fast_realloc(void *ptr, unsigned int *size, size_t min_size)
Reallocate the given block if it is not large enough, otherwise do nothing.
Definition: mem.c:369
#define CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: avcodec.h:713
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:145
int flags
CODEC_FLAG_*.
Definition: avcodec.h:1144
#define CODEC_FLAG_QSCALE
Use fixed qscale.
Definition: avcodec.h:611
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2819
char * av_base64_encode(char *out, int out_size, const uint8_t *in, int in_size)
Encode data to base64 and null-terminate.
Definition: base64.c:72
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:979
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:69
static int get_stats(AVCodecContext *avctx, int eos)
Definition: libtheoraenc.c:89
int bit_rate
the average bitrate
Definition: avcodec.h:1114
#define AV_BASE64_SIZE(x)
Calculate the output size needed to base64-encode x bytes.
Definition: base64.h:59
int width
picture width / height.
Definition: avcodec.h:1229
also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
Definition: pixfmt.h:311
static av_cold int encode_init(AVCodecContext *avc_context)
Definition: libtheoraenc.c:155
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:1761
int ff_alloc_packet(AVPacket *avpkt, int size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1257
NULL
Definition: eval.c:55
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
static av_cold int encode_close(AVCodecContext *avc_context)
Definition: libtheoraenc.c:351
th_enc_ctx * t_state
Definition: libtheoraenc.c:46
int extradata_size
Definition: avcodec.h:1165
#define AV_WB16(p, d)
Definition: intreadwrite.h:213
static int encode_frame(AVCodecContext *avc_context, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: libtheoraenc.c:267
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:1130
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1255
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:65
common internal api header.
common internal and external API header
FF_ENABLE_DEPRECATION_WARNINGS int av_pix_fmt_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift)
Utility function to access log2_chroma_w log2_chroma_h from the pixel format AVPixFmtDescriptor.
Definition: pixdesc.c:1625
int den
denominator
Definition: rational.h:45
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
void * priv_data
Definition: avcodec.h:1092
static int ogg_packet(AVFormatContext *s, int *str, int *dstart, int *dsize, int64_t *fpos)
Definition: oggdec.c:332
AVCodec ff_libtheora_encoder
AVCodec struct exposed to libavcodec.
Definition: libtheoraenc.c:366
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:191
#define FF_QP2LAMBDA
factor to convert from H.263 QP to lambda
Definition: avutil.h:207
int av_base64_decode(uint8_t *out, const char *in, int out_size)
Decode a base64-encoded string.
Definition: base64.c:45
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:972
AVPixelFormat
Pixel format.
Definition: pixfmt.h:63
This structure stores compressed data.
Definition: avcodec.h:950
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:966