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  * $HeadURL$
  19  * $Date$
  20  * $Revision$
  21  * $Author$
  22  */
  23
  24 #define FFMPEG_MODULE "AV-FFmpeg"
  25 #define FFMPEG_MOD_VERSION "0.1.0"
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <errno.h>
  31 #include <stdint.h>
  32
  33 #include <ffmpeg/avformat.h>
  34 #include <ffmpeg/avcodec.h>
  35
  36 #include "../plugin/plugin.h"
  37 #include "../av/avfile.h"
  38 #include "../vfs/vfs.h"
  39 #include "../sys/log.h"
  40
  41 #define init ffmpeg_LTX_init
  42
  43 #define MIN(a,b) (((a)<(b))?(a):(b))
  44
  45 static struct resource {
  46         AVFormatContext *fmt;
  47         AVCodecContext *actx, *vctx;
  48         AVCodec *acodec, *vcodec;
  49         int astream, vstream;
  50
  51         int16_t *aframe;
  52         int aframelen, aframeoff;
  53
  54         struct audio_format afmt;
  55 } *data;
  56 static int datasz = 4;
  57
  58 static struct vfs_access vfs;
  59 static struct log_context logger;
  60
  61 /* 2ooM VFS open handler for libavformat */
  62 static int ff_vfs_open(URLContext *h, const char *filename, int flags)
  63 {
  64         struct vfs_file *f;
  65
  66         strstart(filename, "vfs:", &filename);
  67
  68         /* 2ooM VFS is read-only */
  69         if (flags & URL_RDWR || flags & URL_WRONLY)
  70                 return -EPERM;
  71
  72         if (!(f = vfs.open(filename)))
  73                 return -ENOENT;
  74
  75         h->priv_data = f;
  76
  77         return 0;
  78 }
  79
  80 static int ff_vfs_read(URLContext *h, unsigned char *buf, int size)
  81 {
  82         return vfs.read(h->priv_data, buf, size);
  83 }
  84
  85 static int ff_vfs_write(URLContext *h, unsigned char *buf, int size)
  86 {
  87         return -1; /* 2ooM VFS is read-only */
  88 }
  89
  90 static offset_t ff_vfs_seek(URLContext *h, offset_t pos, int whence)
  91 {
  92         return vfs.seek(h->priv_data, pos, whence);
  93 }
  94
  95 static int ff_vfs_close(URLContext *h)
  96 {
  97         vfs.close(h->priv_data);
  98         return 0;
  99 }
 100
 101 static URLProtocol vfs_protocol = {
 102         "vfs",
 103         ff_vfs_open,
 104         ff_vfs_read,
 105         ff_vfs_write,
 106         ff_vfs_seek,
 107         ff_vfs_close,
 108         NULL
 109 };
 110
 111 /* Double the size of the buffer for storing resources */
 112 static int moreresources(void) {
 113         static int init;
 114         struct resource *new;
 115         int i;
 116
 117         if (!(new = realloc(data, sizeof *data * datasz*2)))
 118                 return -1;
 119
 120         data = new;
 121
 122         for (i = (!init) ? init = 1, 0 : datasz; i < datasz*2; i++)
 123                 data[i].fmt = NULL;
 124
 125         datasz *= 2;
 126
 127         return 0;
 128 }
 129
 130 /* Locate the first stream matching type, initialize codecs, and return the
 131  * stream ID.
 132  */
 133 static int getstream(enum CodecType type, AVCodec **codec, AVFormatContext *fmt)
 134 {
 135         AVCodecContext *ctx;
 136         int i;
 137
 138         for (i = 0; i < fmt->nb_streams; i++)
 139                 if (fmt->streams[i]->codec->codec_type == type)
 140                         break;
 141
 142         if (i >= fmt->nb_streams) {
 143                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 144                              "Failed to find%s stream in %s",
 145                              (type == CODEC_TYPE_AUDIO) ? " audio" :
 146                              (type == CODEC_TYPE_VIDEO) ? " video" : "",
 147                              fmt->filename);
 148                 return -1;
 149         }
 150
 151         ctx = fmt->streams[i]->codec;
 152
 153         if (!(*codec = avcodec_find_decoder(ctx->codec_id))) {
 154                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 155                              "Failed to find decoder for %s", ctx->codec_name);
 156                 return -1;
 157         }
 158
 159         if (avcodec_open(ctx, *codec) < 0) {
 160                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 161                              "Failed to open decoder %s", (*codec)->name);
 162                 return -1;
 163         }
 164
 165         return i;
 166 }
 167
 168 /* Attempt to open a VFS resource with FFmpeg */
 169 static int ff_av_open(const char *resource, int type,
 170                       const struct audio_format *afmt,
 171                       const struct video_format *vfmt)
 172 {
 173         char *url;
 174         struct resource r = { .astream = -1, .vstream = -1 };
 175         int i;
 176
 177         if (!(type & AV_INPUT_AUDIO || type & AV_INPUT_VIDEO))
 178                 return -1;
 179
 180         if (!(url = malloc(strlen("vfs:") + strlen(resource) + 1)))
 181                 return -1;
 182
 183         /* Find a free resource, or make one */
 184         for (i = 0; i < datasz; i++)
 185                 if (data[i].fmt == NULL)
 186                         break;
 187         if (i >= datasz)
 188                 if (moreresources())
 189                         goto err;
 190
 191         strcpy(url, "vfs:");
 192         strcat(url, resource);
 193
 194         if (av_open_input_file(&r.fmt, url, NULL, 0, NULL) != 0) {
 195                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 196                              "Failed to open %s", url);
 197                 goto err;
 198         }
 199
 200         if (av_find_stream_info(r.fmt) < 0) {
 201                 logger.write(LOG_DEBUG, FFMPEG_MODULE,
 202                              "Failed to find stream info for %s", url);
 203                 goto err;
 204         }
 205
 206         if (type & AV_INPUT_AUDIO) {
 207                 r.astream = getstream(CODEC_TYPE_AUDIO, &r.acodec, r.fmt);
 208                 if (r.astream == -1)
 209                         goto err;
 210                 r.actx = r.fmt->streams[r.astream]->codec;
 211                 r.afmt = *afmt;
 212                 if (!(r.aframe = malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE)))
 213                         goto err;
 214         }
 215         if (type & AV_INPUT_VIDEO) {
 216                 r.vstream = getstream(CODEC_TYPE_VIDEO, &r.vcodec, r.fmt);
 217                 if (r.vstream == -1)
 218                         goto err;
 219                 r.vctx = r.fmt->streams[r.vstream]->codec;
 220         }
 221
 222         data[i] = r;
 223         return i;
 224 err:
 225         if (r.actx)
 226                 avcodec_close(r.actx);
 227         if (r.vctx)
 228                 avcodec_close(r.vctx);
 229         if (r.fmt)
 230                 av_close_input_file(r.fmt);
 231
 232         free(r.aframe);
 233
 234         free(url);
 235         return -1;
 236 }
 237
 238 /* Close an open resource */
 239 static void ff_av_close(int id)
 240 {
 241         if (id >= datasz || !data[id].fmt)
 242                 return;
 243
 244         if (data[id].actx)
 245                 avcodec_close(data[id].actx);
 246         if (data[id].vctx)
 247                 avcodec_close(data[id].vctx);
 248
 249         av_close_input_file(data[id].fmt);
 250         data[id].fmt = NULL;
 251
 252         free(data[id].aframe);
 253
 254         return;
 255 }
 256
 257 /* Read decoded audio data */
 258 static int ff_av_read_audio(int id, void *buf, int len)
 259 {
 260         struct resource *d;
 261         int written = 0;
 262         char *stream = buf;
 263
 264         if (id >= datasz || !data[id].fmt || data[id].astream == -1)
 265                 return -1;
 266
 267         d = &data[id];
 268
 269         if (d->aframeoff < d->aframelen) {
 270                 if (d->aframelen - d->aframeoff >= len) {
 271                         memcpy(stream, d->aframe+(d->aframeoff/2), len);
 272                         d->aframeoff += len;
 273                         written += len;
 274                         return written;
 275                 } else {
 276                         memcpy(stream, d->aframe+(d->aframeoff/2),
 277                                        d->aframelen - d->aframeoff);
 278
 279                         written += d->aframelen - d->aframeoff;
 280                         len     -= d->aframelen - d->aframeoff;
 281                         stream  += d->aframelen - d->aframeoff;
 282                 }
 283         }
 284
 285         while (len > 0) {
 286                 AVPacket packet;
 287                 d->aframelen = 0, d->aframeoff = 0;
 288                 if (av_read_frame(d->fmt, &packet) < 0)
 289                         break;
 290
 291                 if (packet.stream_index == d->astream) {
 292                         d->aframelen = AVCODEC_MAX_AUDIO_FRAME_SIZE;
 293                         avcodec_decode_audio2(d->actx, d->aframe, &d->aframelen,
 294                                               packet.data, packet.size);
 295
 296                         if (d->aframelen <= 0)
 297                                 return av_free_packet(&packet), written;
 298
 299                         memcpy(stream, d->aframe, MIN(len, d->aframelen));
 300
 301                         d->aframeoff += MIN(len, d->aframelen);
 302                         stream       += MIN(len, d->aframelen);
 303                         written      += MIN(len, d->aframelen);
 304                         len          -= MIN(len, d->aframelen);
 305                 }
 306
 307                 av_free_packet(&packet);
 308         }
 309
 310         return written;
 311 }
 312
 313 static int ff_av_rewind(int id)
 314 {
 315         if (id >= datasz || !data[id].fmt)
 316                 return -1;
 317
 318         if (av_seek_frame(data[id].fmt, -1, 0, AVSEEK_FLAG_BYTE) < 0)
 319                 return -1;
 320
 321         return 0;
 322 }
 323
 324 int init(plugin_useservice_t useservice)
 325 {
 326         static struct av_accessor av = {
 327                 .open = ff_av_open,
 328                 .close = ff_av_close,
 329                 .read_audio = ff_av_read_audio,
 330                 .rewind = ff_av_rewind,
 331         };
 332
 333         if (useservice(LOG_SERVICE, FFMPEG_MODULE, &logger))
 334                 return -1;
 335
 336         if (useservice(VFSACCESS_SERVICE, FFMPEG_MODULE, &vfs))
 337                 return -1;
 338
 339         if (useservice(AV_PLUGIN_SERVICE, FFMPEG_MODULE, &av))
 340                 return -1;
 341
 342         if (moreresources())
 343                 return -1;
 344
 345         av_register_all();
 346         register_protocol(&vfs_protocol);
 347
 348         logger.write(LOG_INFO, FFMPEG_MODULE,
 349                      "libavformat/libavcodec media input " FFMPEG_MOD_VERSION);
 350
 351         return 0;
 352 }
 353
 354