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libavcodec/libtheoraenc.c

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00001 /*
00002  * Copyright (c) 2006 Paul Richards <paul.richards@gmail.com>
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00033 /* FFmpeg includes */
00034 #include "libavutil/intreadwrite.h"
00035 #include "libavutil/log.h"
00036 #include "libavutil/base64.h"
00037 #include "avcodec.h"
00038 
00039 /* libtheora includes */
00040 #include <theora/theoraenc.h>
00041 
00042 typedef struct TheoraContext {
00043     th_enc_ctx *t_state;
00044     uint8_t    *stats;
00045     int         stats_size;
00046     int         stats_offset;
00047     int         uv_hshift;
00048     int         uv_vshift;
00049     int         keyframe_mask;
00050 } TheoraContext;
00051 
00053 static int concatenate_packet(unsigned int* offset,
00054                               AVCodecContext* avc_context,
00055                               const ogg_packet* packet)
00056 {
00057     const char* message = NULL;
00058     uint8_t* newdata    = NULL;
00059     int newsize = avc_context->extradata_size + 2 + packet->bytes;
00060 
00061     if (packet->bytes < 0) {
00062         message = "ogg_packet has negative size";
00063     } else if (packet->bytes > 0xffff) {
00064         message = "ogg_packet is larger than 65535 bytes";
00065     } else if (newsize < avc_context->extradata_size) {
00066         message = "extradata_size would overflow";
00067     } else {
00068         newdata = av_realloc(avc_context->extradata, newsize);
00069         if (!newdata)
00070             message = "av_realloc failed";
00071     }
00072     if (message) {
00073         av_log(avc_context, AV_LOG_ERROR, "concatenate_packet failed: %s\n", message);
00074         return -1;
00075     }
00076 
00077     avc_context->extradata      = newdata;
00078     avc_context->extradata_size = newsize;
00079     AV_WB16(avc_context->extradata + (*offset), packet->bytes);
00080     *offset += 2;
00081     memcpy(avc_context->extradata + (*offset), packet->packet, packet->bytes);
00082     (*offset) += packet->bytes;
00083     return 0;
00084 }
00085 
00086 static int get_stats(AVCodecContext *avctx, int eos)
00087 {
00088 #ifdef TH_ENCCTL_2PASS_OUT
00089     TheoraContext *h = avctx->priv_data;
00090     uint8_t *buf;
00091     int bytes;
00092 
00093     bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_OUT, &buf, sizeof(buf));
00094     if (bytes < 0) {
00095         av_log(avctx, AV_LOG_ERROR, "Error getting first pass stats\n");
00096         return -1;
00097     }
00098     if (!eos) {
00099         h->stats = av_fast_realloc(h->stats, &h->stats_size,
00100                                    h->stats_offset + bytes);
00101         memcpy(h->stats + h->stats_offset, buf, bytes);
00102         h->stats_offset += bytes;
00103     } else {
00104         int b64_size = ((h->stats_offset + 2) / 3) * 4 + 1;
00105         // libtheora generates a summary header at the end
00106         memcpy(h->stats, buf, bytes);
00107         avctx->stats_out = av_malloc(b64_size);
00108         av_base64_encode(avctx->stats_out, b64_size, h->stats, h->stats_offset);
00109     }
00110     return 0;
00111 #else
00112     av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
00113     return -1;
00114 #endif
00115 }
00116 
00117 // libtheora won't read the entire buffer we give it at once, so we have to
00118 // repeatedly submit it...
00119 static int submit_stats(AVCodecContext *avctx)
00120 {
00121 #ifdef TH_ENCCTL_2PASS_IN
00122     TheoraContext *h = avctx->priv_data;
00123     int bytes;
00124     if (!h->stats) {
00125         if (!avctx->stats_in) {
00126             av_log(avctx, AV_LOG_ERROR, "No statsfile for second pass\n");
00127             return -1;
00128         }
00129         h->stats_size = strlen(avctx->stats_in) * 3/4;
00130         h->stats      = av_malloc(h->stats_size);
00131         h->stats_size = av_base64_decode(h->stats, avctx->stats_in, h->stats_size);
00132     }
00133     while (h->stats_size - h->stats_offset > 0) {
00134         bytes = th_encode_ctl(h->t_state, TH_ENCCTL_2PASS_IN,
00135                               h->stats + h->stats_offset,
00136                               h->stats_size - h->stats_offset);
00137         if (bytes < 0) {
00138             av_log(avctx, AV_LOG_ERROR, "Error submitting stats\n");
00139             return -1;
00140         }
00141         if (!bytes)
00142             return 0;
00143         h->stats_offset += bytes;
00144     }
00145     return 0;
00146 #else
00147     av_log(avctx, AV_LOG_ERROR, "libtheora too old to support 2pass\n");
00148     return -1;
00149 #endif
00150 }
00151 
00152 static av_cold int encode_init(AVCodecContext* avc_context)
00153 {
00154     th_info t_info;
00155     th_comment t_comment;
00156     ogg_packet o_packet;
00157     unsigned int offset;
00158     TheoraContext *h = avc_context->priv_data;
00159     uint32_t gop_size = avc_context->gop_size;
00160 
00161     /* Set up the theora_info struct */
00162     th_info_init(&t_info);
00163     t_info.frame_width  = FFALIGN(avc_context->width,  16);
00164     t_info.frame_height = FFALIGN(avc_context->height, 16);
00165     t_info.pic_width    = avc_context->width;
00166     t_info.pic_height   = avc_context->height;
00167     t_info.pic_x        = 0;
00168     t_info.pic_y        = 0;
00169     /* Swap numerator and denominator as time_base in AVCodecContext gives the
00170      * time period between frames, but theora_info needs the framerate.  */
00171     t_info.fps_numerator   = avc_context->time_base.den;
00172     t_info.fps_denominator = avc_context->time_base.num;
00173     if (avc_context->sample_aspect_ratio.num) {
00174         t_info.aspect_numerator   = avc_context->sample_aspect_ratio.num;
00175         t_info.aspect_denominator = avc_context->sample_aspect_ratio.den;
00176     } else {
00177         t_info.aspect_numerator   = 1;
00178         t_info.aspect_denominator = 1;
00179     }
00180 
00181     if (avc_context->color_primaries == AVCOL_PRI_BT470M)
00182         t_info.colorspace = TH_CS_ITU_REC_470M;
00183     else if (avc_context->color_primaries == AVCOL_PRI_BT470BG)
00184         t_info.colorspace = TH_CS_ITU_REC_470BG;
00185     else
00186         t_info.colorspace = TH_CS_UNSPECIFIED;
00187 
00188     if (avc_context->pix_fmt == PIX_FMT_YUV420P)
00189         t_info.pixel_fmt = TH_PF_420;
00190     else if (avc_context->pix_fmt == PIX_FMT_YUV422P)
00191         t_info.pixel_fmt = TH_PF_422;
00192     else if (avc_context->pix_fmt == PIX_FMT_YUV444P)
00193         t_info.pixel_fmt = TH_PF_444;
00194     else {
00195         av_log(avc_context, AV_LOG_ERROR, "Unsupported pix_fmt\n");
00196         return -1;
00197     }
00198     avcodec_get_chroma_sub_sample(avc_context->pix_fmt, &h->uv_hshift, &h->uv_vshift);
00199 
00200     if (avc_context->flags & CODEC_FLAG_QSCALE) {
00201         /* to be constant with the libvorbis implementation, clip global_quality to 0 - 10
00202            Theora accepts a quality parameter p, which is:
00203                 * 0 <= p <=63
00204                 * an int value
00205          */
00206         t_info.quality        = av_clip(avc_context->global_quality / (float)FF_QP2LAMBDA, 0, 10) * 6.3;
00207         t_info.target_bitrate = 0;
00208     } else {
00209         t_info.target_bitrate = avc_context->bit_rate;
00210         t_info.quality        = 0;
00211     }
00212 
00213     /* Now initialise libtheora */
00214     h->t_state = th_encode_alloc(&t_info);
00215     if (!h->t_state) {
00216         av_log(avc_context, AV_LOG_ERROR, "theora_encode_init failed\n");
00217         return -1;
00218     }
00219 
00220     h->keyframe_mask = (1 << t_info.keyframe_granule_shift) - 1;
00221     /* Clear up theora_info struct */
00222     th_info_clear(&t_info);
00223 
00224     if (th_encode_ctl(h->t_state, TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE,
00225                       &gop_size, sizeof(gop_size))) {
00226         av_log(avc_context, AV_LOG_ERROR, "Error setting GOP size\n");
00227         return -1;
00228     }
00229 
00230     // need to enable 2 pass (via TH_ENCCTL_2PASS_) before encoding headers
00231     if (avc_context->flags & CODEC_FLAG_PASS1) {
00232         if (get_stats(avc_context, 0))
00233             return -1;
00234     } else if (avc_context->flags & CODEC_FLAG_PASS2) {
00235         if (submit_stats(avc_context))
00236             return -1;
00237     }
00238 
00239     /*
00240         Output first header packet consisting of theora
00241         header, comment, and tables.
00242 
00243         Each one is prefixed with a 16bit size, then they
00244         are concatenated together into ffmpeg's extradata.
00245     */
00246     offset = 0;
00247 
00248     /* Headers */
00249     th_comment_init(&t_comment);
00250 
00251     while (th_encode_flushheader(h->t_state, &t_comment, &o_packet))
00252         if (concatenate_packet(&offset, avc_context, &o_packet))
00253             return -1;
00254 
00255     th_comment_clear(&t_comment);
00256 
00257     /* Set up the output AVFrame */
00258     avc_context->coded_frame= avcodec_alloc_frame();
00259 
00260     return 0;
00261 }
00262 
00263 static int encode_frame(AVCodecContext* avc_context, uint8_t *outbuf,
00264                         int buf_size, void *data)
00265 {
00266     th_ycbcr_buffer t_yuv_buffer;
00267     TheoraContext *h = avc_context->priv_data;
00268     AVFrame *frame = data;
00269     ogg_packet o_packet;
00270     int result, i;
00271 
00272     // EOS, finish and get 1st pass stats if applicable
00273     if (!frame) {
00274         th_encode_packetout(h->t_state, 1, &o_packet);
00275         if (avc_context->flags & CODEC_FLAG_PASS1)
00276             if (get_stats(avc_context, 1))
00277                 return -1;
00278         return 0;
00279     }
00280 
00281     /* Copy planes to the theora yuv_buffer */
00282     for (i = 0; i < 3; i++) {
00283         t_yuv_buffer[i].width  = FFALIGN(avc_context->width,  16) >> (i && h->uv_hshift);
00284         t_yuv_buffer[i].height = FFALIGN(avc_context->height, 16) >> (i && h->uv_vshift);
00285         t_yuv_buffer[i].stride = frame->linesize[i];
00286         t_yuv_buffer[i].data   = frame->data[i];
00287     }
00288 
00289     if (avc_context->flags & CODEC_FLAG_PASS2)
00290         if (submit_stats(avc_context))
00291             return -1;
00292 
00293     /* Now call into theora_encode_YUVin */
00294     result = th_encode_ycbcr_in(h->t_state, t_yuv_buffer);
00295     if (result) {
00296         const char* message;
00297         switch (result) {
00298         case -1:
00299             message = "differing frame sizes";
00300             break;
00301         case TH_EINVAL:
00302             message = "encoder is not ready or is finished";
00303             break;
00304         default:
00305             message = "unknown reason";
00306             break;
00307         }
00308         av_log(avc_context, AV_LOG_ERROR, "theora_encode_YUVin failed (%s) [%d]\n", message, result);
00309         return -1;
00310     }
00311 
00312     if (avc_context->flags & CODEC_FLAG_PASS1)
00313         if (get_stats(avc_context, 0))
00314             return -1;
00315 
00316     /* Pick up returned ogg_packet */
00317     result = th_encode_packetout(h->t_state, 0, &o_packet);
00318     switch (result) {
00319     case 0:
00320         /* No packet is ready */
00321         return 0;
00322     case 1:
00323         /* Success, we have a packet */
00324         break;
00325     default:
00326         av_log(avc_context, AV_LOG_ERROR, "theora_encode_packetout failed [%d]\n", result);
00327         return -1;
00328     }
00329 
00330     /* Copy ogg_packet content out to buffer */
00331     if (buf_size < o_packet.bytes) {
00332         av_log(avc_context, AV_LOG_ERROR, "encoded frame too large\n");
00333         return -1;
00334     }
00335     memcpy(outbuf, o_packet.packet, o_packet.bytes);
00336 
00337     // HACK: assumes no encoder delay, this is true until libtheora becomes
00338     // multithreaded (which will be disabled unless explictly requested)
00339     avc_context->coded_frame->pts = frame->pts;
00340     avc_context->coded_frame->key_frame = !(o_packet.granulepos & h->keyframe_mask);
00341 
00342     return o_packet.bytes;
00343 }
00344 
00345 static av_cold int encode_close(AVCodecContext* avc_context)
00346 {
00347     TheoraContext *h = avc_context->priv_data;
00348 
00349     th_encode_free(h->t_state);
00350     av_freep(&h->stats);
00351     av_freep(&avc_context->coded_frame);
00352     av_freep(&avc_context->stats_out);
00353     av_freep(&avc_context->extradata);
00354     avc_context->extradata_size = 0;
00355 
00356     return 0;
00357 }
00358 
00360 AVCodec libtheora_encoder = {
00361     .name = "libtheora",
00362     .type = AVMEDIA_TYPE_VIDEO,
00363     .id = CODEC_ID_THEORA,
00364     .priv_data_size = sizeof(TheoraContext),
00365     .init = encode_init,
00366     .close = encode_close,
00367     .encode = encode_frame,
00368     .capabilities = CODEC_CAP_DELAY, // needed to get the statsfile summary
00369     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_YUV422P, PIX_FMT_YUV444P, PIX_FMT_NONE},
00370     .long_name = NULL_IF_CONFIG_SMALL("libtheora Theora"),
00371 };

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