src/module/ffmpeg.c

   1 /*  2ooM: The Master of Orion II Reverse Engineering Project
   2  *  Copyright (C) 2006 Nick Bowler
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program; if not, write to the Free Software
  16  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  17  */
  18
  19 #define FFMPEG_MODULE "AV-FFmpeg"
  20 #define FFMPEG_MOD_VERSION "0.1.0"
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <errno.h>
  26 #include <stdint.h>
  27
  28 #include <libavformat/avformat.h>
  29 #include <libavcodec/avcodec.h>
  30 #include <libavutil/avstring.h>
  31
  32 #include "../plugin/plugin.h"
  33 #include "../av/avfile.h"
  34 #include "../vfs/vfs.h"
  35 #include "../sys/log.h"
  36
  37 #define init ffmpeg_LTX_init
  38
  39 #define MIN(a,b) (((a)<(b))?(a):(b))
  40
  41 static struct resource {
  42         AVFormatContext *fmt;
  43         AVCodecContext *actx, *vctx;
  44         AVCodec *acodec, *vcodec;
  45         int astream, vstream;
  46
  47         int16_t *aframe;
  48         int aframelen, aframeoff;
  49
  50         struct audio_format afmt;
  51 } *data;
  52 static int datasz = 4;
  53
  54 static struct vfs_access vfs;
  55 static struct log_context logger;
  56
  57 /* 2ooM VFS open handler for libavformat */
  58 static int ff_vfs_open(URLContext *h, const char *filename, int flags)
  59 {
  60         struct vfs_file *f;
  61
  62         av_strstart(filename, "vfs:", &filename);
  63
  64         /* 2ooM VFS is read-only */
  65         if (flags & URL_RDWR || flags & URL_WRONLY)
  66                 return -EPERM;
  67
  68         if (!(f = vfs.open(filename)))
  69                 return -ENOENT;
  70
  71         h->priv_data = f;
  72
  73         return 0;
  74 }
  75
  76 static int ff_vfs_read(URLContext *h, unsigned char *buf, int size)
  77 {
  78         return vfs.read(h->priv_data, buf, size);
  79 }
  80
  81 static int ff_vfs_write(URLContext *h, unsigned char *buf, int size)
  82 {
  83         return -1; /* 2ooM VFS is read-only */
  84 }
  85
  86 static offset_t ff_vfs_seek(URLContext *h, offset_t pos, int whence)
  87 {
  88         return vfs.seek(h->priv_data, pos, whence);
  89 }
  90
  91 static int ff_vfs_close(URLContext *h)
  92 {
  93         vfs.close(h->priv_data);
  94         return 0;
  95 }
  96
  97 static URLProtocol vfs_protocol = {
  98         .name      = "vfs",
  99         .url_open  = ff_vfs_open,
 100         .url_read  = ff_vfs_read,
 101         .url_write = ff_vfs_write,
 102         .url_seek  = ff_vfs_seek,
 103         .url_close = ff_vfs_close,
 104 };
 105
 106 /* Double the size of the buffer for storing resources */
 107 static int moreresources(void) {
 108         static int init;
 109         struct resource *new;
 110         int i;
 111
 112         if (!(new = realloc(data, sizeof *data * datasz*2)))
 113                 return -1;
 114
 115         data = new;
 116
 117         for (i = (!init) ? init = 1, 0 : datasz; i < datasz*2; i++)
 118                 data[i].fmt = NULL;
 119
 120         datasz *= 2;
 121
 122         return 0;
 123 }
 124
 125 /* Locate the first stream matching type, initialize codecs, and return the
 126  * stream ID.
 127  */
 128 static int getstream(enum CodecType type, AVCodec **codec, AVFormatContext *fmt)
 129 {
 130         AVCodecContext *ctx;
 131         int i;
 132
 133         for (i = 0; i < fmt->nb_streams; i++)
 134                 if (fmt->streams[i]->codec->codec_type == type)
 135                         break;
 136
 137         if (i >= fmt->nb_streams) {
 138                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 139                              "Failed to find%s stream in %s",
 140                              (type == CODEC_TYPE_AUDIO) ? " audio" :
 141                              (type == CODEC_TYPE_VIDEO) ? " video" : "",
 142                              fmt->filename);
 143                 return -1;
 144         }
 145
 146         ctx = fmt->streams[i]->codec;
 147
 148         if (!(*codec = avcodec_find_decoder(ctx->codec_id))) {
 149                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 150                              "Failed to find decoder for %s", ctx->codec_name);
 151                 return -1;
 152         }
 153
 154         if (avcodec_open(ctx, *codec) < 0) {
 155                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 156                              "Failed to open decoder %s", (*codec)->name);
 157                 return -1;
 158         }
 159
 160         return i;
 161 }
 162
 163 /* Attempt to open a VFS resource with FFmpeg */
 164 static int ff_av_open(const char *resource, int type,
 165                       const struct audio_format *afmt,
 166                       const struct video_format *vfmt)
 167 {
 168         char *url;
 169         struct resource r = { .astream = -1, .vstream = -1 };
 170         int i;
 171
 172         if (!(type & AV_INPUT_AUDIO || type & AV_INPUT_VIDEO))
 173                 return -1;
 174
 175         if (!(url = malloc(strlen("vfs:") + strlen(resource) + 1)))
 176                 return -1;
 177
 178         /* Find a free resource, or make one */
 179         for (i = 0; i < datasz; i++)
 180                 if (data[i].fmt == NULL)
 181                         break;
 182         if (i >= datasz)
 183                 if (moreresources())
 184                         goto err;
 185
 186         strcpy(url, "vfs:");
 187         strcat(url, resource);
 188
 189         if (av_open_input_file(&r.fmt, url, NULL, 0, NULL) != 0) {
 190                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 191                              "Failed to open %s", url);
 192                 goto err;
 193         }
 194
 195         if (av_find_stream_info(r.fmt) < 0) {
 196                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 197                              "Failed to find stream info for %s", url);
 198                 goto err;
 199         }
 200
 201         if (type & AV_INPUT_AUDIO) {
 202                 r.astream = getstream(CODEC_TYPE_AUDIO, &r.acodec, r.fmt);
 203                 if (r.astream == -1)
 204                         goto err;
 205                 r.actx = r.fmt->streams[r.astream]->codec;
 206                 r.afmt = *afmt;
 207                 if (!(r.aframe = malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE)))
 208                         goto err;
 209         }
 210         if (type & AV_INPUT_VIDEO) {
 211                 r.vstream = getstream(CODEC_TYPE_VIDEO, &r.vcodec, r.fmt);
 212                 if (r.vstream == -1)
 213                         goto err;
 214                 r.vctx = r.fmt->streams[r.vstream]->codec;
 215         }
 216
 217         data[i] = r;
 218         return i;
 219 err:
 220         if (r.actx)
 221                 avcodec_close(r.actx);
 222         if (r.vctx)
 223                 avcodec_close(r.vctx);
 224         if (r.fmt)
 225                 av_close_input_file(r.fmt);
 226
 227         free(r.aframe);
 228
 229         free(url);
 230         return -1;
 231 }
 232
 233 /* Close an open resource */
 234 static void ff_av_close(int id)
 235 {
 236         if (id >= datasz || !data[id].fmt)
 237                 return;
 238
 239         if (data[id].actx)
 240                 avcodec_close(data[id].actx);
 241         if (data[id].vctx)
 242                 avcodec_close(data[id].vctx);
 243
 244         av_close_input_file(data[id].fmt);
 245         data[id].fmt = NULL;
 246
 247         free(data[id].aframe);
 248
 249         return;
 250 }
 251
 252 /* Read decoded audio data */
 253 static int ff_av_read_audio(int id, void *buf, int len)
 254 {
 255         struct resource *d;
 256         int written = 0;
 257         char *stream = buf;
 258
 259         if (id >= datasz || !data[id].fmt || data[id].astream == -1)
 260                 return -1;
 261
 262         d = &data[id];
 263
 264         if (d->aframeoff < d->aframelen) {
 265                 if (d->aframelen - d->aframeoff >= len) {
 266                         memcpy(stream, d->aframe+(d->aframeoff/2), len);
 267                         d->aframeoff += len;
 268                         written += len;
 269                         return written;
 270                 } else {
 271                         memcpy(stream, d->aframe+(d->aframeoff/2),
 272                                        d->aframelen - d->aframeoff);
 273
 274                         written += d->aframelen - d->aframeoff;
 275                         len     -= d->aframelen - d->aframeoff;
 276                         stream  += d->aframelen - d->aframeoff;
 277                 }
 278         }
 279
 280         while (len > 0) {
 281                 AVPacket packet;
 282                 d->aframelen = 0, d->aframeoff = 0;
 283                 if (av_read_frame(d->fmt, &packet) < 0)
 284                         break;
 285
 286                 if (packet.stream_index == d->astream) {
 287                         d->aframelen = AVCODEC_MAX_AUDIO_FRAME_SIZE;
 288                         avcodec_decode_audio2(d->actx, d->aframe, &d->aframelen,
 289                                               packet.data, packet.size);
 290
 291                         if (d->aframelen <= 0)
 292                                 return av_free_packet(&packet), written;
 293
 294                         memcpy(stream, d->aframe, MIN(len, d->aframelen));
 295
 296                         d->aframeoff += MIN(len, d->aframelen);
 297                         stream       += MIN(len, d->aframelen);
 298                         written      += MIN(len, d->aframelen);
 299                         len          -= MIN(len, d->aframelen);
 300                 }
 301
 302                 av_free_packet(&packet);
 303         }
 304
 305         return written;
 306 }
 307
 308 static int ff_av_rewind(int id)
 309 {
 310         if (id >= datasz || !data[id].fmt)
 311                 return -1;
 312
 313         if (av_seek_frame(data[id].fmt, -1, 0, AVSEEK_FLAG_BYTE) < 0)
 314                 return -1;
 315
 316         return 0;
 317 }
 318
 319 int init(plugin_useservice_t useservice)
 320 {
 321         static struct av_accessor av = {
 322                 .open = ff_av_open,
 323                 .close = ff_av_close,
 324                 .read_audio = ff_av_read_audio,
 325                 .rewind = ff_av_rewind,
 326         };
 327
 328         if (useservice(LOG_SERVICE, FFMPEG_MODULE, &logger))
 329                 return -1;
 330
 331         if (useservice(VFSACCESS_SERVICE, FFMPEG_MODULE, &vfs))
 332                 return -1;
 333
 334         if (useservice(AV_PLUGIN_SERVICE, FFMPEG_MODULE, &av))
 335                 return -1;
 336
 337         if (moreresources())
 338                 return -1;
 339
 340         av_register_all();
 341         register_protocol(&vfs_protocol);
 342
 343         logger.write(LOG_INFO, FFMPEG_MODULE,
 344                      "libavformat/libavcodec media input " FFMPEG_MOD_VERSION);
 345
 346         return 0;
 347 }
 348
 349