libavformat/libnut.c
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00001 /*
00002  * NUT (de)muxing via libnut
00003  * copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00028 #include "avformat.h"
00029 #include "internal.h"
00030 #include "riff.h"
00031 #include <libnut.h>
00032 
00033 #define ID_STRING "nut/multimedia container"
00034 #define ID_LENGTH (strlen(ID_STRING) + 1)
00035 
00036 typedef struct {
00037     nut_context_tt * nut;
00038     nut_stream_header_tt * s;
00039 } NUTContext;
00040 
00041 static const AVCodecTag nut_tags[] = {
00042     { CODEC_ID_MPEG4,  MKTAG('m', 'p', '4', 'v') },
00043     { CODEC_ID_MP3,    MKTAG('m', 'p', '3', ' ') },
00044     { CODEC_ID_VORBIS, MKTAG('v', 'r', 'b', 's') },
00045     { 0, 0 },
00046 };
00047 
00048 #if CONFIG_LIBNUT_MUXER
00049 static int av_write(void * h, size_t len, const uint8_t * buf) {
00050     AVIOContext * bc = h;
00051     avio_write(bc, buf, len);
00052     //avio_flush(bc);
00053     return len;
00054 }
00055 
00056 static int nut_write_header(AVFormatContext * avf) {
00057     NUTContext * priv = avf->priv_data;
00058     AVIOContext * bc = avf->pb;
00059     nut_muxer_opts_tt mopts = {
00060         .output = {
00061             .priv = bc,
00062             .write = av_write,
00063         },
00064         .alloc = { av_malloc, av_realloc, av_free },
00065         .write_index = 1,
00066         .realtime_stream = 0,
00067         .max_distance = 32768,
00068         .fti = NULL,
00069     };
00070     nut_stream_header_tt * s;
00071     int i;
00072 
00073     priv->s = s = av_mallocz((avf->nb_streams + 1) * sizeof*s);
00074     if(!s)
00075         return AVERROR(ENOMEM);
00076 
00077     for (i = 0; i < avf->nb_streams; i++) {
00078         AVCodecContext * codec = avf->streams[i]->codec;
00079         int j;
00080         int fourcc = 0;
00081         int num, denom, ssize;
00082 
00083         s[i].type = codec->codec_type == AVMEDIA_TYPE_VIDEO ? NUT_VIDEO_CLASS : NUT_AUDIO_CLASS;
00084 
00085         if (codec->codec_tag) fourcc = codec->codec_tag;
00086         else fourcc = ff_codec_get_tag(nut_tags, codec->codec_id);
00087 
00088         if (!fourcc) {
00089             if (codec->codec_type == AVMEDIA_TYPE_VIDEO) fourcc = ff_codec_get_tag(ff_codec_bmp_tags, codec->codec_id);
00090             if (codec->codec_type == AVMEDIA_TYPE_AUDIO) fourcc = ff_codec_get_tag(ff_codec_wav_tags, codec->codec_id);
00091         }
00092 
00093         s[i].fourcc_len = 4;
00094         s[i].fourcc = av_malloc(s[i].fourcc_len);
00095         for (j = 0; j < s[i].fourcc_len; j++) s[i].fourcc[j] = (fourcc >> (j*8)) & 0xFF;
00096 
00097         ff_parse_specific_params(codec, &num, &ssize, &denom);
00098         avpriv_set_pts_info(avf->streams[i], 60, denom, num);
00099 
00100         s[i].time_base.num = denom;
00101         s[i].time_base.den = num;
00102 
00103         s[i].fixed_fps = 0;
00104         s[i].decode_delay = codec->has_b_frames;
00105         s[i].codec_specific_len = codec->extradata_size;
00106         s[i].codec_specific = codec->extradata;
00107 
00108         if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00109             s[i].width = codec->width;
00110             s[i].height = codec->height;
00111             s[i].sample_width = 0;
00112             s[i].sample_height = 0;
00113             s[i].colorspace_type = 0;
00114         } else {
00115             s[i].samplerate_num = codec->sample_rate;
00116             s[i].samplerate_denom = 1;
00117             s[i].channel_count = codec->channels;
00118         }
00119     }
00120 
00121     s[avf->nb_streams].type = -1;
00122     priv->nut = nut_muxer_init(&mopts, s, NULL);
00123 
00124     return 0;
00125 }
00126 
00127 static int nut_write_packet(AVFormatContext * avf, AVPacket * pkt) {
00128     NUTContext * priv = avf->priv_data;
00129     nut_packet_tt p;
00130 
00131     p.len = pkt->size;
00132     p.stream = pkt->stream_index;
00133     p.pts = pkt->pts;
00134     p.flags = pkt->flags & AV_PKT_FLAG_KEY ? NUT_FLAG_KEY : 0;
00135     p.next_pts = 0;
00136 
00137     nut_write_frame_reorder(priv->nut, &p, pkt->data);
00138 
00139     return 0;
00140 }
00141 
00142 static int nut_write_trailer(AVFormatContext * avf) {
00143     AVIOContext * bc = avf->pb;
00144     NUTContext * priv = avf->priv_data;
00145     int i;
00146 
00147     nut_muxer_uninit_reorder(priv->nut);
00148     avio_flush(bc);
00149 
00150     for(i = 0; priv->s[i].type != -1; i++ ) av_freep(&priv->s[i].fourcc);
00151     av_freep(&priv->s);
00152 
00153     return 0;
00154 }
00155 
00156 AVOutputFormat ff_libnut_muxer = {
00157     .name              = "libnut",
00158     .long_name         = "nut format",
00159     .mime_type         = "video/x-nut",
00160     .extensions        = "nut",
00161     .priv_data_size    = sizeof(NUTContext),
00162     .audio_codec       = CODEC_ID_VORBIS,
00163     .video_codec       = CODEC_ID_MPEG4,
00164     .write_header      = nut_write_header,
00165     .write_packet      = nut_write_packet,
00166     .write_trailer     = nut_write_trailer,
00167     .flags = AVFMT_GLOBALHEADER,
00168 };
00169 #endif /* CONFIG_LIBNUT_MUXER */
00170 
00171 static int nut_probe(AVProbeData *p) {
00172     if (!memcmp(p->buf, ID_STRING, ID_LENGTH)) return AVPROBE_SCORE_MAX;
00173 
00174     return 0;
00175 }
00176 
00177 static size_t av_read(void * h, size_t len, uint8_t * buf) {
00178     AVIOContext * bc = h;
00179     return avio_read(bc, buf, len);
00180 }
00181 
00182 static off_t av_seek(void * h, long long pos, int whence) {
00183     AVIOContext * bc = h;
00184     if (whence == SEEK_END) {
00185         pos = avio_size(bc) + pos;
00186         whence = SEEK_SET;
00187     }
00188     return avio_seek(bc, pos, whence);
00189 }
00190 
00191 static int nut_read_header(AVFormatContext * avf, AVFormatParameters * ap) {
00192     NUTContext * priv = avf->priv_data;
00193     AVIOContext * bc = avf->pb;
00194     nut_demuxer_opts_tt dopts = {
00195         .input = {
00196             .priv = bc,
00197             .seek = av_seek,
00198             .read = av_read,
00199             .eof = NULL,
00200             .file_pos = 0,
00201         },
00202         .alloc = { av_malloc, av_realloc, av_free },
00203         .read_index = 1,
00204         .cache_syncpoints = 1,
00205     };
00206     nut_context_tt * nut = priv->nut = nut_demuxer_init(&dopts);
00207     nut_stream_header_tt * s;
00208     int ret, i;
00209 
00210     if(!nut)
00211         return -1;
00212 
00213     if ((ret = nut_read_headers(nut, &s, NULL))) {
00214         av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
00215         nut_demuxer_uninit(nut);
00216         priv->nut = NULL;
00217         return -1;
00218     }
00219 
00220     priv->s = s;
00221 
00222     for (i = 0; s[i].type != -1 && i < 2; i++) {
00223         AVStream * st = avformat_new_stream(avf, NULL);
00224         int j;
00225 
00226         for (j = 0; j < s[i].fourcc_len && j < 8; j++) st->codec->codec_tag |= s[i].fourcc[j]<<(j*8);
00227 
00228         st->codec->has_b_frames = s[i].decode_delay;
00229 
00230         st->codec->extradata_size = s[i].codec_specific_len;
00231         if (st->codec->extradata_size) {
00232             st->codec->extradata = av_mallocz(st->codec->extradata_size);
00233             if(!st->codec->extradata){
00234                 nut_demuxer_uninit(nut);
00235                 priv->nut = NULL;
00236                 return AVERROR(ENOMEM);
00237             }
00238             memcpy(st->codec->extradata, s[i].codec_specific, st->codec->extradata_size);
00239         }
00240 
00241         avpriv_set_pts_info(avf->streams[i], 60, s[i].time_base.num, s[i].time_base.den);
00242         st->start_time = 0;
00243         st->duration = s[i].max_pts;
00244 
00245         st->codec->codec_id = ff_codec_get_id(nut_tags, st->codec->codec_tag);
00246 
00247         switch(s[i].type) {
00248         case NUT_AUDIO_CLASS:
00249             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00250             if (st->codec->codec_id == CODEC_ID_NONE) st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, st->codec->codec_tag);
00251 
00252             st->codec->channels = s[i].channel_count;
00253             st->codec->sample_rate = s[i].samplerate_num / s[i].samplerate_denom;
00254             break;
00255         case NUT_VIDEO_CLASS:
00256             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00257             if (st->codec->codec_id == CODEC_ID_NONE) st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, st->codec->codec_tag);
00258 
00259             st->codec->width = s[i].width;
00260             st->codec->height = s[i].height;
00261             st->sample_aspect_ratio.num = s[i].sample_width;
00262             st->sample_aspect_ratio.den = s[i].sample_height;
00263             break;
00264         }
00265         if (st->codec->codec_id == CODEC_ID_NONE) av_log(avf, AV_LOG_ERROR, "Unknown codec?!\n");
00266     }
00267 
00268     return 0;
00269 }
00270 
00271 static int nut_read_packet(AVFormatContext * avf, AVPacket * pkt) {
00272     NUTContext * priv = avf->priv_data;
00273     nut_packet_tt pd;
00274     int ret;
00275 
00276     ret = nut_read_next_packet(priv->nut, &pd);
00277 
00278     if (ret || av_new_packet(pkt, pd.len) < 0) {
00279         if (ret != NUT_ERR_EOF)
00280             av_log(avf, AV_LOG_ERROR, " NUT error: %s\n", nut_error(ret));
00281         return -1;
00282     }
00283 
00284     if (pd.flags & NUT_FLAG_KEY) pkt->flags |= AV_PKT_FLAG_KEY;
00285     pkt->pts = pd.pts;
00286     pkt->stream_index = pd.stream;
00287     pkt->pos = avio_tell(avf->pb);
00288 
00289     ret = nut_read_frame(priv->nut, &pd.len, pkt->data);
00290 
00291     return ret;
00292 }
00293 
00294 static int nut_read_seek(AVFormatContext * avf, int stream_index, int64_t target_ts, int flags) {
00295     NUTContext * priv = avf->priv_data;
00296     int active_streams[] = { stream_index, -1 };
00297     double time_pos = target_ts * priv->s[stream_index].time_base.num / (double)priv->s[stream_index].time_base.den;
00298 
00299     if (nut_seek(priv->nut, time_pos, 2*!(flags & AVSEEK_FLAG_BACKWARD), active_streams)) return -1;
00300 
00301     return 0;
00302 }
00303 
00304 static int nut_read_close(AVFormatContext *s) {
00305     NUTContext * priv = s->priv_data;
00306 
00307     nut_demuxer_uninit(priv->nut);
00308 
00309     return 0;
00310 }
00311 
00312 AVInputFormat ff_libnut_demuxer = {
00313     .name           = "libnut",
00314     .long_name      = NULL_IF_CONFIG_SMALL("NUT format"),
00315     .priv_data_size = sizeof(NUTContext),
00316     .read_probe     = nut_probe,
00317     .read_header    = nut_read_header,
00318     .read_packet    = nut_read_packet,
00319     .read_close     = nut_read_close,
00320     .read_seek      = nut_read_seek,
00321     .extensions = "nut",
00322 };