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libtheoraenc.c
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1 /*
2  * Copyright (c) 2006 Paul Richards <paul.richards@gmail.com>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * @brief Theora encoder using libtheora.
24  * @author Paul Richards <paul.richards@gmail.com>
25  *
26  * A lot of this is copy / paste from other output codecs in
27  * libavcodec or pure guesswork (or both).
28  *
29  * I have used t_ prefixes on variables which are libtheora types
30  * and o_ prefixes on variables which are libogg types.
31  */
32 
33 /* FFmpeg 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 
55 /** Concatenate an ogg_packet into the extradata. */
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 AVERROR_EXTERNAL;
100  }
101  if (!eos) {
102  void *tmp = av_fast_realloc(h->stats, &h->stats_size,
103  h->stats_offset + bytes);
104  if (!tmp)
105  return AVERROR(ENOMEM);
106  h->stats = tmp;
107  memcpy(h->stats + h->stats_offset, buf, bytes);
108  h->stats_offset += bytes;
109  } else {
110  int b64_size = AV_BASE64_SIZE(h->stats_offset);
111  // libtheora generates a summary header at the end
112  memcpy(h->stats, buf, bytes);
113  avctx->stats_out = av_malloc(b64_size);
114  if (!avctx->stats_out)
115  return AVERROR(ENOMEM);
116  av_base64_encode(avctx->stats_out, b64_size, h->stats, h->stats_offset);
117  }
118  return 0;
119 #else
120  av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
121  return AVERROR(ENOSUP);
122 #endif
123 }
124 
125 // libtheora won't read the entire buffer we give it at once, so we have to
126 // repeatedly submit it...
127 static int submit_stats(AVCodecContext *avctx)
128 {
129 #ifdef TH_ENCCTL_2PASS_IN
130  TheoraContext *h = avctx->priv_data;
131  int bytes;
132  if (!h->stats) {
133  if (!avctx->stats_in) {
134  av_log(avctx, AV_LOG_ERROR, "No statsfile for second pass\n");
135  return AVERROR(EINVAL);
136  }
137  h->stats_size = strlen(avctx->stats_in) * 3/4;
138  h->stats = av_malloc(h->stats_size);
139  if (!h->stats) {
140  h->stats_size = 0;
141  return AVERROR(ENOMEM);
142  }
143  h->stats_size = av_base64_decode(h->stats, avctx->stats_in, h->stats_size);
144  }
145  while (h->stats_size - h->stats_offset > 0) {
146  bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_IN,
147  h->stats + h->stats_offset,
148  h->stats_size - h->stats_offset);
149  if (bytes < 0) {
150  av_log(avctx, AV_LOG_ERROR, "Error submitting stats\n");
151  return AVERROR_EXTERNAL;
152  }
153  if (!bytes)
154  return 0;
155  h->stats_offset += bytes;
156  }
157  return 0;
158 #else
159  av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
160  return AVERROR(ENOSUP);
161 #endif
162 }
163 
164 static av_cold int encode_init(AVCodecContext* avc_context)
165 {
166  th_info t_info;
167  th_comment t_comment;
168  ogg_packet o_packet;
169  unsigned int offset;
170  TheoraContext *h = avc_context->priv_data;
171  uint32_t gop_size = avc_context->gop_size;
172  int ret;
173 
174  /* Set up the theora_info struct */
175  th_info_init(&t_info);
176  t_info.frame_width = FFALIGN(avc_context->width, 16);
177  t_info.frame_height = FFALIGN(avc_context->height, 16);
178  t_info.pic_width = avc_context->width;
179  t_info.pic_height = avc_context->height;
180  t_info.pic_x = 0;
181  t_info.pic_y = 0;
182  /* Swap numerator and denominator as time_base in AVCodecContext gives the
183  * time period between frames, but theora_info needs the framerate. */
184  t_info.fps_numerator = avc_context->time_base.den;
185  t_info.fps_denominator = avc_context->time_base.num;
186  if (avc_context->sample_aspect_ratio.num) {
187  t_info.aspect_numerator = avc_context->sample_aspect_ratio.num;
188  t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
189  } else {
190  t_info.aspect_numerator = 1;
191  t_info.aspect_denominator = 1;
192  }
193 
194  if (avc_context->color_primaries == AVCOL_PRI_BT470M)
195  t_info.colorspace = TH_CS_ITU_REC_470M;
196  else if (avc_context->color_primaries == AVCOL_PRI_BT470BG)
197  t_info.colorspace = TH_CS_ITU_REC_470BG;
198  else
199  t_info.colorspace = TH_CS_UNSPECIFIED;
200 
201  if (avc_context->pix_fmt == AV_PIX_FMT_YUV420P)
202  t_info.pixel_fmt = TH_PF_420;
203  else if (avc_context->pix_fmt == AV_PIX_FMT_YUV422P)
204  t_info.pixel_fmt = TH_PF_422;
205  else if (avc_context->pix_fmt == AV_PIX_FMT_YUV444P)
206  t_info.pixel_fmt = TH_PF_444;
207  else {
208  av_log(avc_context, AV_LOG_ERROR, "Unsupported pix_fmt\n");
209  return AVERROR(EINVAL);
210  }
212 
213  if (avc_context->flags & AV_CODEC_FLAG_QSCALE) {
214  /* Clip global_quality in QP units to the [0 - 10] range
215  to be consistent with the libvorbis implementation.
216  Theora accepts a quality parameter which is an int value in
217  the [0 - 63] range.
218  */
219  t_info.quality = av_clipf(avc_context->global_quality / (float)FF_QP2LAMBDA, 0, 10) * 6.3;
220  t_info.target_bitrate = 0;
221  } else {
222  t_info.target_bitrate = avc_context->bit_rate;
223  t_info.quality = 0;
224  }
225 
226  /* Now initialise libtheora */
227  h->t_state = th_encode_alloc(&t_info);
228  if (!h->t_state) {
229  av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
230  return AVERROR_EXTERNAL;
231  }
232 
233  h->keyframe_mask = (1 << t_info.keyframe_granule_shift) - 1;
234  /* Clear up theora_info struct */
235  th_info_clear(&t_info);
236 
237  if (th_encode_ctl(h->t_state, TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
238  &gop_size, sizeof(gop_size))) {
239  av_log(avc_context, AV_LOG_ERROR, "Error setting GOP size\n");
240  return AVERROR_EXTERNAL;
241  }
242 
243  // need to enable 2 pass (via TH_ENCCTL_2PASS_) before encoding headers
244  if (avc_context->flags & AV_CODEC_FLAG_PASS1) {
245  if ((ret = get_stats(avc_context, 0)) < 0)
246  return ret;
247  } else if (avc_context->flags & AV_CODEC_FLAG_PASS2) {
248  if ((ret = submit_stats(avc_context)) < 0)
249  return ret;
250  }
251 
252  /*
253  Output first header packet consisting of theora
254  header, comment, and tables.
255 
256  Each one is prefixed with a 16-bit size, then they
257  are concatenated together into libavcodec's extradata.
258  */
259  offset = 0;
260 
261  /* Headers */
262  th_comment_init(&t_comment);
263 
264  while (th_encode_flushheader(h->t_state, &t_comment, &o_packet))
265  if ((ret = concatenate_packet(&offset, avc_context, &o_packet)) < 0)
266  return ret;
267 
268  th_comment_clear(&t_comment);
269 
270  return 0;
271 }
272 
273 static int encode_frame(AVCodecContext* avc_context, AVPacket *pkt,
274  const AVFrame *frame, int *got_packet)
275 {
276  th_ycbcr_buffer t_yuv_buffer;
277  TheoraContext *h = avc_context->priv_data;
278  ogg_packet o_packet;
279  int result, i, ret;
280 
281  // EOS, finish and get 1st pass stats if applicable
282  if (!frame) {
283  th_encode_packetout(h->t_state, 1, &o_packet);
284  if (avc_context->flags & AV_CODEC_FLAG_PASS1)
285  if ((ret = get_stats(avc_context, 1)) < 0)
286  return ret;
287  return 0;
288  }
289 
290  /* Copy planes to the theora yuv_buffer */
291  for (i = 0; i < 3; i++) {
292  t_yuv_buffer[i].width = FFALIGN(avc_context->width, 16) >> (i && h->uv_hshift);
293  t_yuv_buffer[i].height = FFALIGN(avc_context->height, 16) >> (i && h->uv_vshift);
294  t_yuv_buffer[i].stride = frame->linesize[i];
295  t_yuv_buffer[i].data = frame->data[i];
296  }
297 
298  if (avc_context->flags & AV_CODEC_FLAG_PASS2)
299  if ((ret = submit_stats(avc_context)) < 0)
300  return ret;
301 
302  /* Now call into theora_encode_YUVin */
303  result = th_encode_ycbcr_in(h->t_state, t_yuv_buffer);
304  if (result) {
305  const char* message;
306  switch (result) {
307  case -1:
308  message = "differing frame sizes";
309  break;
310  case TH_EINVAL:
311  message = "encoder is not ready or is finished";
312  break;
313  default:
314  message = "unknown reason";
315  break;
316  }
317  av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
318  return AVERROR_EXTERNAL;
319  }
320 
321  if (avc_context->flags & AV_CODEC_FLAG_PASS1)
322  if ((ret = get_stats(avc_context, 0)) < 0)
323  return ret;
324 
325  /* Pick up returned ogg_packet */
326  result = th_encode_packetout(h->t_state, 0, &o_packet);
327  switch (result) {
328  case 0:
329  /* No packet is ready */
330  return 0;
331  case 1:
332  /* Success, we have a packet */
333  break;
334  default:
335  av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
336  return AVERROR_EXTERNAL;
337  }
338 
339  /* Copy ogg_packet content out to buffer */
340  if ((ret = ff_alloc_packet2(avc_context, pkt, o_packet.bytes, 0)) < 0)
341  return ret;
342  memcpy(pkt->data, o_packet.packet, o_packet.bytes);
343 
344  // HACK: assumes no encoder delay, this is true until libtheora becomes
345  // multithreaded (which will be disabled unless explicitly requested)
346  pkt->pts = pkt->dts = frame->pts;
347 #if FF_API_CODED_FRAME
349  avc_context->coded_frame->key_frame = !(o_packet.granulepos & h->keyframe_mask);
351 #endif
352  if (!(o_packet.granulepos & h->keyframe_mask))
353  pkt->flags |= AV_PKT_FLAG_KEY;
354  *got_packet = 1;
355 
356  return 0;
357 }
358 
359 static av_cold int encode_close(AVCodecContext* avc_context)
360 {
361  TheoraContext *h = avc_context->priv_data;
362 
363  th_encode_free(h->t_state);
364  av_freep(&h->stats);
365  av_freep(&avc_context->stats_out);
366  av_freep(&avc_context->extradata);
367  avc_context->extradata_size = 0;
368 
369  return 0;
370 }
371 
372 /** AVCodec struct exposed to libavcodec */
374  .name = "libtheora",
375  .long_name = NULL_IF_CONFIG_SMALL("libtheora Theora"),
376  .type = AVMEDIA_TYPE_VIDEO,
377  .id = AV_CODEC_ID_THEORA,
378  .priv_data_size = sizeof(TheoraContext),
379  .init = encode_init,
380  .close = encode_close,
381  .encode2 = encode_frame,
382  .capabilities = AV_CODEC_CAP_DELAY, // needed to get the statsfile summary
383  .pix_fmts = (const enum AVPixelFormat[]){
385  },
386 };
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
uint8_t * stats
Definition: libtheoraenc.c:47
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:67
int64_t bit_rate
the average bitrate
Definition: avcodec.h:1722
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
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:2068
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1885
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:2833
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3559
static int submit_stats(AVCodecContext *avctx)
Definition: libtheoraenc.c:127
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1794
#define AV_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:981
uint8_t
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:268
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1772
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1588
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:2825
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1620
also FCC Title 47 Code of Federal Regulations 73.682 (a)(20)
Definition: pixfmt.h:396
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
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:480
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1752
const char * name
Name of the codec implementation.
Definition: avcodec.h:3566
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
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:138
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1594
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:66
int gop_size
Definition: movenc.c:66
static int get_stats(AVCodecContext *avctx, int eos)
Definition: libtheoraenc.c:89
#define AV_CODEC_FLAG_QSCALE
Use fixed qscale.
Definition: avcodec.h:830
#define AV_BASE64_SIZE(x)
Calculate the output size needed to base64-encode x bytes to a null-terminated string.
Definition: base64.h:66
int width
picture width / height.
Definition: avcodec.h:1844
also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
Definition: pixfmt.h:398
static av_cold int encode_init(AVCodecContext *avc_context)
Definition: libtheoraenc.c:164
#define AV_CODEC_FLAG_PASS1
Use internal 2pass ratecontrol in first pass mode.
Definition: avcodec.h:846
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:2372
void avcodec_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: imgconvert.c:38
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:215
static int ogg_packet(AVFormatContext *s, int *sid, int *dstart, int *dsize, int64_t *fpos)
find the next Ogg packet
Definition: oggdec.c:458
main external API structure.
Definition: avcodec.h:1657
static av_cold int encode_close(AVCodecContext *avc_context)
Definition: libtheoraenc.c:359
th_enc_ctx * t_state
Definition: libtheoraenc.c:46
void * buf
Definition: avisynth_c.h:553
int extradata_size
Definition: avcodec.h:1773
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: utils.c:1690
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:262
static int encode_frame(AVCodecContext *avc_context, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: libtheoraenc.c:273
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:1738
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:198
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1870
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:62
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:80
common internal api header.
common internal and external API header
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:187
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:3078
int den
denominator
Definition: rational.h:45
#define AV_CODEC_FLAG_PASS2
Use internal 2pass ratecontrol in second pass mode.
Definition: avcodec.h:850
void * priv_data
Definition: avcodec.h:1699
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:81
static uint8_t tmp[8]
Definition: des.c:38
AVCodec ff_libtheora_encoder
AVCodec struct exposed to libavcodec.
Definition: libtheoraenc.c:373
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:253
#define FF_QP2LAMBDA
factor to convert from H.263 QP to lambda
Definition: avutil.h:219
int av_base64_decode(uint8_t *out, const char *in_str, int out_size)
Decode a base64-encoded string.
Definition: base64.c:79
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1587
#define av_freep(p)
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:57
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1565
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1581