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