2 * Copyright (c) 2006 Paul Richards <paul.richards@gmail.com>
4 * This file is part of FFmpeg.
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.
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.
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
22 * \file libtheoraenc.c
23 * \brief Theora encoder using libtheora.
24 * \author Paul Richards <paul.richards@gmail.com>
26 * A lot of this is copy / paste from other output codecs in
27 * libavcodec or pure guesswork (or both).
29 * I have used t_ prefixes on variables which are libtheora types
30 * and o_ prefixes on variables which are libogg types.
34 #include "libavutil/intreadwrite.h"
35 #include "libavutil/log.h"
38 /* libtheora includes */
39 #include <theora/theoraenc.h>
41 typedef struct TheoraContext {
46 Concatenates an ogg_packet into the extradata.
48 static int concatenate_packet(unsigned int* offset,
49 AVCodecContext* avc_context,
50 const ogg_packet* packet)
52 const char* message = NULL;
53 uint8_t* newdata = NULL;
54 int newsize = avc_context->extradata_size + 2 + packet->bytes;
56 if (packet->bytes < 0) {
57 message = "ogg_packet has negative size";
58 } else if (packet->bytes > 0xffff) {
59 message = "ogg_packet is larger than 65535 bytes";
60 } else if (newsize < avc_context->extradata_size) {
61 message = "extradata_size would overflow";
63 newdata = av_realloc(avc_context->extradata, newsize);
65 message = "av_realloc failed";
68 av_log(avc_context, AV_LOG_ERROR, "concatenate_packet failed: %s\n", message);
72 avc_context->extradata = newdata;
73 avc_context->extradata_size = newsize;
74 AV_WB16(avc_context->extradata + (*offset), packet->bytes);
76 memcpy(avc_context->extradata + (*offset), packet->packet, packet->bytes);
77 (*offset) += packet->bytes;
81 static av_cold int encode_init(AVCodecContext* avc_context)
87 TheoraContext *h = avc_context->priv_data;
88 uint32_t gop_size = avc_context->gop_size;
90 /* Set up the theora_info struct */
91 th_info_init(&t_info);
92 t_info.frame_width = FFALIGN(avc_context->width, 16);
93 t_info.frame_height = FFALIGN(avc_context->height, 16);
94 t_info.pic_width = avc_context->width;
95 t_info.pic_height = avc_context->height;
98 /* Swap numerator and denominator as time_base in AVCodecContext gives the
99 * time period between frames, but theora_info needs the framerate. */
100 t_info.fps_numerator = avc_context->time_base.den;
101 t_info.fps_denominator = avc_context->time_base.num;
102 if (avc_context->sample_aspect_ratio.num) {
103 t_info.aspect_numerator = avc_context->sample_aspect_ratio.num;
104 t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
106 t_info.aspect_numerator = 1;
107 t_info.aspect_denominator = 1;
109 t_info.colorspace = TH_CS_UNSPECIFIED;
110 t_info.pixel_fmt = TH_PF_420;
112 if (avc_context->flags & CODEC_FLAG_QSCALE) {
113 /* to be constant with the libvorbis implementation, clip global_quality to 0 - 10
114 Theora accepts a quality parameter p, which is:
118 t_info.quality = av_clip(avc_context->global_quality / (float)FF_QP2LAMBDA, 0, 10) * 6.3;
119 t_info.target_bitrate = 0;
121 t_info.target_bitrate = avc_context->bit_rate;
125 /* Now initialise libtheora */
126 h->t_state = th_encode_alloc(&t_info);
128 av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
132 /* Clear up theora_info struct */
133 th_info_clear(&t_info);
135 if (th_encode_ctl(h->t_state, TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
136 &gop_size, sizeof(gop_size))) {
137 av_log(avc_context, AV_LOG_ERROR, "Error setting GOP size\n");
142 Output first header packet consisting of theora
143 header, comment, and tables.
145 Each one is prefixed with a 16bit size, then they
146 are concatenated together into ffmpeg's extradata.
151 th_comment_init(&t_comment);
153 while (th_encode_flushheader(h->t_state, &t_comment, &o_packet))
154 if (concatenate_packet(&offset, avc_context, &o_packet))
157 th_comment_clear(&t_comment);
159 /* Set up the output AVFrame */
160 avc_context->coded_frame= avcodec_alloc_frame();
165 static int encode_frame(AVCodecContext* avc_context, uint8_t *outbuf,
166 int buf_size, void *data)
168 th_ycbcr_buffer t_yuv_buffer;
169 TheoraContext *h = avc_context->priv_data;
170 AVFrame *frame = data;
174 assert(avc_context->pix_fmt == PIX_FMT_YUV420P);
176 /* Copy planes to the theora yuv_buffer */
177 for (i = 0; i < 3; i++) {
178 t_yuv_buffer[i].width = FFALIGN(avc_context->width, 16) >> !!i;
179 t_yuv_buffer[i].height = FFALIGN(avc_context->height, 16) >> !!i;
180 t_yuv_buffer[i].stride = frame->linesize[i];
181 t_yuv_buffer[i].data = frame->data[i];
184 /* Now call into theora_encode_YUVin */
185 result = th_encode_ycbcr_in(h->t_state, t_yuv_buffer);
190 message = "differing frame sizes";
193 message = "encoder is not ready or is finished";
196 message = "unknown reason";
199 av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
203 /* Pick up returned ogg_packet */
204 result = th_encode_packetout(h->t_state, 0, &o_packet);
207 /* No packet is ready */
210 /* Success, we have a packet */
213 av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
217 /* Copy ogg_packet content out to buffer */
218 if (buf_size < o_packet.bytes) {
219 av_log(avc_context, AV_LOG_ERROR, "encoded frame too large\n");
222 memcpy(outbuf, o_packet.packet, o_packet.bytes);
224 // HACK: does not take codec delay into account (neither does the decoder though)
225 avc_context->coded_frame->pts = frame->pts;
227 return o_packet.bytes;
230 static av_cold int encode_close(AVCodecContext* avc_context)
233 TheoraContext *h = avc_context->priv_data;
237 result = th_encode_packetout(h->t_state, 1, &o_packet);
238 th_encode_free(h->t_state);
239 av_freep(&avc_context->coded_frame);
240 av_freep(&avc_context->extradata);
241 avc_context->extradata_size = 0;
244 case 0: /* No packet is ready */
245 case -1: /* Encoding finished */
248 /* We have a packet */
249 message = "gave us a packet";
252 message = "unknown reason";
255 av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed (%s) [%d]\n", message, result);
259 static const enum PixelFormat supported_pixel_formats[] = { PIX_FMT_YUV420P, PIX_FMT_NONE };
261 /*! AVCodec struct exposed to libavcodec */
262 AVCodec libtheora_encoder = {
264 .type = CODEC_TYPE_VIDEO,
265 .id = CODEC_ID_THEORA,
266 .priv_data_size = sizeof(TheoraContext),
268 .close = encode_close,
269 .encode = encode_frame,
270 .pix_fmts = supported_pixel_formats,
271 .long_name = NULL_IF_CONFIG_SMALL("libtheora Theora"),