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 St, Fifth Floor, Boston, MA 02110-1301 USA
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.
37 /* libtheora includes */
38 #include <theora/theora.h>
40 typedef struct TheoraContext{
45 Concatenates an ogg_packet into the extradata.
47 static int concatenate_packet(unsigned int* offset, AVCodecContext* avc_context, const ogg_packet* packet)
50 uint8_t* newdata = NULL;
51 int newsize = avc_context->extradata_size + 2 + packet->bytes;
53 if (packet->bytes < 0) {
54 message = "ogg_packet has negative size";
55 } else if (packet->bytes > 0xffff) {
56 message = "ogg_packet is larger than 65535 bytes";
57 } else if (newsize < avc_context->extradata_size) {
58 message = "extradata_size would overflow";
60 newdata = av_realloc(avc_context->extradata, newsize);
61 if (newdata == NULL) {
62 message = "av_realloc failed";
65 if (message != NULL) {
66 av_log(avc_context, AV_LOG_ERROR, "concatenate_packet failed: %s\n", message);
70 avc_context->extradata = newdata;
71 avc_context->extradata_size = newsize;
72 avc_context->extradata[ (*offset)++ ] = packet->bytes >> 8;
73 avc_context->extradata[ (*offset)++ ] = packet->bytes & 0xff;
74 memcpy( avc_context->extradata + (*offset), packet->packet, packet->bytes );
75 (*offset) += packet->bytes;
79 static int encode_init(AVCodecContext* avc_context)
82 theora_comment t_comment;
85 TheoraContext *h = avc_context->priv_data;
87 /* Set up the theora_info struct */
88 theora_info_init( &t_info );
89 t_info.width = avc_context->width;
90 t_info.height = avc_context->height;
91 t_info.frame_width = avc_context->width;
92 t_info.frame_height = avc_context->height;
95 t_info.fps_numerator = avc_context->time_base.den;
96 t_info.fps_denominator = avc_context->time_base.num;
97 if (avc_context->sample_aspect_ratio.num != 0) {
98 t_info.aspect_numerator = avc_context->sample_aspect_ratio.num;
99 t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
101 t_info.aspect_numerator = 1;
102 t_info.aspect_denominator = 1;
104 t_info.colorspace = OC_CS_UNSPECIFIED;
105 t_info.pixelformat = OC_PF_420;
106 t_info.target_bitrate = avc_context->bit_rate;
107 t_info.keyframe_frequency = avc_context->gop_size;
108 t_info.keyframe_frequency_force = avc_context->gop_size;
109 t_info.keyframe_mindistance = avc_context->keyint_min;
113 t_info.dropframes_p = 0;
114 t_info.keyframe_auto_p = 1;
115 t_info.keyframe_data_target_bitrate = t_info.target_bitrate * 1.5;
116 t_info.keyframe_auto_threshold = 80;
117 t_info.noise_sensitivity = 1;
118 t_info.sharpness = 0;
120 /* Now initialise libtheora */
121 if (theora_encode_init( &(h->t_state), &t_info ) != 0) {
122 av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
126 /* Clear up theora_info struct */
127 theora_info_clear( &t_info );
130 Output first header packet consisting of theora
131 header, comment, and tables.
133 Each one is prefixed with a 16bit size, then they
134 are concatenated together into ffmpeg's extradata.
139 theora_encode_header( &(h->t_state), &o_packet );
140 if (concatenate_packet( &offset, avc_context, &o_packet ) != 0) {
145 theora_comment_init( &t_comment );
146 theora_encode_comment( &t_comment, &o_packet );
147 if (concatenate_packet( &offset, avc_context, &o_packet ) != 0) {
152 theora_encode_tables( &(h->t_state), &o_packet );
153 if (concatenate_packet( &offset, avc_context, &o_packet ) != 0) {
157 /* Clear up theora_comment struct */
158 theora_comment_clear( &t_comment );
160 /* Set up the output AVFrame */
161 avc_context->coded_frame= avcodec_alloc_frame();
166 static int encode_frame(
167 AVCodecContext* avc_context,
172 yuv_buffer t_yuv_buffer;
173 TheoraContext *h = avc_context->priv_data;
174 AVFrame *frame = data;
178 assert(avc_context->pix_fmt == PIX_FMT_YUV420P);
180 /* Copy planes to the theora yuv_buffer */
181 if (frame->linesize[1] != frame->linesize[2]) {
182 av_log(avc_context, AV_LOG_ERROR, "U and V stride differ\n");
186 t_yuv_buffer.y_width = avc_context->width;
187 t_yuv_buffer.y_height = avc_context->height;
188 t_yuv_buffer.y_stride = frame->linesize[0];
189 t_yuv_buffer.uv_width = t_yuv_buffer.y_width / 2;
190 t_yuv_buffer.uv_height = t_yuv_buffer.y_height / 2;
191 t_yuv_buffer.uv_stride = frame->linesize[1];
193 t_yuv_buffer.y = frame->data[0];
194 t_yuv_buffer.u = frame->data[1];
195 t_yuv_buffer.v = frame->data[2];
197 /* Now call into theora_encode_YUVin */
198 result = theora_encode_YUVin( &(h->t_state), &t_yuv_buffer );
203 message = "differing frame sizes";
206 message = "encoder is not ready or is finished";
209 message = "unknown reason";
212 av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
216 /* Pick up returned ogg_packet */
217 result = theora_encode_packetout( &(h->t_state), 0, &o_packet );
220 /* No packet is ready */
223 /* Success, we have a packet */
226 av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
230 /* Copy ogg_packet content out to buffer */
231 if (buf_size < o_packet.bytes) {
232 av_log(avc_context, AV_LOG_ERROR, "encoded frame too large\n");
235 memcpy(outbuf, o_packet.packet, o_packet.bytes);
237 return o_packet.bytes;
240 static int encode_close(AVCodecContext* avc_context)
243 TheoraContext *h = avc_context->priv_data;
247 result = theora_encode_packetout( &(h->t_state), 1, &o_packet );
248 theora_clear( &(h->t_state) );
250 case 0:/* No packet is ready */
251 case -1:/* Encoding finished */
254 /* We have a packet */
255 message = "gave us a packet";
258 message = "unknown reason";
261 av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed (%s) [%d]\n", message, result);
265 static const enum PixelFormat supported_pixel_formats[] = { PIX_FMT_YUV420P, -1 };
267 /*! AVCodec struct exposed to libavcodec */
268 AVCodec libtheora_encoder =
271 .type = CODEC_TYPE_VIDEO,
272 .id = CODEC_ID_THEORA,
273 .priv_data_size = sizeof(TheoraContext),
275 .close = encode_close,
276 .encode = encode_frame,
277 .pix_fmts = supported_pixel_formats,