libavformat/rsoenc.c

   1 /*
   2  * RSO muxer
   3  * Copyright (c) 2001 Fabrice Bellard (original AU code)
   4  * Copyright (c) 2010 Rafael Carre
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * Libav is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with Libav; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "avformat.h"
  24 #include "internal.h"
  25 #include "riff.h"
  26 #include "rso.h"
  27
  28 static int rso_write_header(AVFormatContext *s)
  29 {
  30     AVIOContext  *pb  = s->pb;
  31     AVCodecContext *enc = s->streams[0]->codec;
  32
  33     if (!enc->codec_tag)
  34         return AVERROR_INVALIDDATA;
  35
  36     if (enc->channels != 1) {
  37         av_log(s, AV_LOG_ERROR, "RSO only supports mono\n");
  38         return AVERROR_INVALIDDATA;
  39     }
  40
  41     if (!s->pb->seekable) {
  42         av_log(s, AV_LOG_ERROR, "muxer does not support non seekable output\n");
  43         return AVERROR_INVALIDDATA;
  44     }
  45
  46     /* XXX: find legal sample rates (if any) */
  47     if (enc->sample_rate >= 1u<<16) {
  48         av_log(s, AV_LOG_ERROR, "Sample rate must be < 65536\n");
  49         return AVERROR_INVALIDDATA;
  50     }
  51
  52     if (enc->codec_id == AV_CODEC_ID_ADPCM_IMA_WAV) {
  53         av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
  54         return AVERROR_PATCHWELCOME;
  55     }
  56
  57     /* format header */
  58     avio_wb16(pb, enc->codec_tag);   /* codec ID */
  59     avio_wb16(pb, 0);                /* data size, will be written at EOF */
  60     avio_wb16(pb, enc->sample_rate);
  61     avio_wb16(pb, 0x0000);           /* play mode ? (0x0000 = don't loop) */
  62
  63     avio_flush(pb);
  64
  65     return 0;
  66 }
  67
  68 static int rso_write_packet(AVFormatContext *s, AVPacket *pkt)
  69 {
  70     avio_write(s->pb, pkt->data, pkt->size);
  71     return 0;
  72 }
  73
  74 static int rso_write_trailer(AVFormatContext *s)
  75 {
  76     AVIOContext *pb = s->pb;
  77     int64_t file_size;
  78     uint16_t coded_file_size;
  79
  80     file_size = avio_tell(pb);
  81
  82     if (file_size < 0)
  83         return file_size;
  84
  85     if (file_size > 0xffff + RSO_HEADER_SIZE) {
  86         av_log(s, AV_LOG_WARNING,
  87                "Output file is too big (%"PRId64" bytes >= 64kB)\n", file_size);
  88         coded_file_size = 0xffff;
  89     } else {
  90         coded_file_size = file_size - RSO_HEADER_SIZE;
  91     }
  92
  93     /* update file size */
  94     avio_seek(pb, 2, SEEK_SET);
  95     avio_wb16(pb, coded_file_size);
  96     avio_seek(pb, file_size, SEEK_SET);
  97
  98     return 0;
  99 }
 100
 101 AVOutputFormat ff_rso_muxer = {
 102     .name           =   "rso",
 103     .long_name      =   NULL_IF_CONFIG_SMALL("Lego Mindstorms RSO"),
 104     .extensions     =   "rso",
 105     .audio_codec    =   AV_CODEC_ID_PCM_U8,
 106     .video_codec    =   AV_CODEC_ID_NONE,
 107     .write_header   =   rso_write_header,
 108     .write_packet   =   rso_write_packet,
 109     .write_trailer  =   rso_write_trailer,
 110     .codec_tag      =   (const AVCodecTag* const []){ff_codec_rso_tags, 0},
 111 };