1/* 2 * NSP demuxer 3 * Copyright (c) 2017 Paul B Mahol 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/avstring.h" 23#include "libavutil/intreadwrite.h" 24#include "avformat.h" 25#include "internal.h" 26#include "pcm.h" 27 28static int nsp_probe(const AVProbeData *p) 29{ 30 if (AV_RB32(p->buf) == AV_RB32("FORM") && 31 AV_RB32(p->buf + 4) == AV_RB32("DS16")) 32 return AVPROBE_SCORE_MAX; 33 return 0; 34} 35 36static int nsp_read_header(AVFormatContext *s) 37{ 38 int channels = 0, rate = 0; 39 uint32_t chunk, size; 40 AVStream *st; 41 int64_t pos; 42 43 avio_skip(s->pb, 12); 44 st = avformat_new_stream(s, NULL); 45 if (!st) 46 return AVERROR(ENOMEM); 47 48 while (!avio_feof(s->pb)) { 49 char value[1024]; 50 51 chunk = avio_rb32(s->pb); 52 size = avio_rl32(s->pb); 53 pos = avio_tell(s->pb); 54 55 switch (chunk) { 56 case MKBETAG('H', 'E', 'D', 'R'): 57 case MKBETAG('H', 'D', 'R', '8'): 58 if (size < 32) 59 return AVERROR_INVALIDDATA; 60 avio_skip(s->pb, 20); 61 rate = avio_rl32(s->pb); 62 avio_skip(s->pb, size - (avio_tell(s->pb) - pos)); 63 break; 64 case MKBETAG('N', 'O', 'T', 'E'): 65 avio_get_str(s->pb, size, value, sizeof(value)); 66 av_dict_set(&s->metadata, "Comment", value, 0); 67 avio_skip(s->pb, size & 1); 68 break; 69 case MKBETAG('S', 'D', 'A', 'B'): 70 channels = 2; 71 break; 72 case MKBETAG('S', 'D', '_', '2'): 73 case MKBETAG('S', 'D', '_', '3'): 74 case MKBETAG('S', 'D', '_', '4'): 75 case MKBETAG('S', 'D', '_', '5'): 76 case MKBETAG('S', 'D', '_', '6'): 77 case MKBETAG('S', 'D', '_', '7'): 78 case MKBETAG('S', 'D', '_', '8'): 79 av_log(s, AV_LOG_WARNING, "Unsupported chunk!\n"); 80 case MKBETAG('S', 'D', 'A', '_'): 81 case MKBETAG('S', 'D', '_', 'A'): 82 channels = 1; 83 break; 84 } 85 86 if (channels) 87 break; 88 } 89 90 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; 91 st->codecpar->ch_layout.nb_channels = channels; 92 st->codecpar->sample_rate = rate; 93 st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE; 94 st->codecpar->block_align = 2 * channels; 95 96 return 0; 97} 98 99const AVInputFormat ff_nsp_demuxer = { 100 .name = "nsp", 101 .long_name = NULL_IF_CONFIG_SMALL("Computerized Speech Lab NSP"), 102 .read_probe = nsp_probe, 103 .read_header = nsp_read_header, 104 .read_packet = ff_pcm_read_packet, 105 .read_seek = ff_pcm_read_seek, 106 .extensions = "nsp", 107 .flags = AVFMT_GENERIC_INDEX, 108}; 109