/* * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * libgme demuxer */ #include #include "libavutil/avstring.h" #include "libavutil/eval.h" #include "libavutil/opt.h" #include "avformat.h" #include "internal.h" typedef struct GMEContext { const AVClass *class; Music_Emu *music_emu; /* options */ int track_index; int sample_rate; int64_t max_size; } GMEContext; #define OFFSET(x) offsetof(GMEContext, x) #define A AV_OPT_FLAG_AUDIO_PARAM #define D AV_OPT_FLAG_DECODING_PARAM static const AVOption options[] = { {"track_index", "set track that should be played", OFFSET(track_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, A|D}, {"sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 44100}, 1000, 999999, A|D}, {"max_size", "set max file size supported (in bytes)", OFFSET(max_size), AV_OPT_TYPE_INT64, {.i64 = 50 * 1024 * 1024}, 0, SIZE_MAX, A|D}, {NULL} }; static void add_meta(AVFormatContext *s, const char *name, const char *value) { if (value && value[0]) av_dict_set(&s->metadata, name, value, 0); } static int load_metadata(AVFormatContext *s, int64_t *duration) { GMEContext *gme = s->priv_data; gme_info_t *info = NULL; char buf[30]; if (gme_track_info(gme->music_emu, &info, gme->track_index)) return AVERROR_STREAM_NOT_FOUND; *duration = info->length; add_meta(s, "system", info->system); add_meta(s, "game", info->game); add_meta(s, "song", info->song); add_meta(s, "author", info->author); add_meta(s, "copyright", info->copyright); add_meta(s, "comment", info->comment); add_meta(s, "dumper", info->dumper); snprintf(buf, sizeof(buf), "%d", (int)gme_track_count(gme->music_emu)); add_meta(s, "tracks", buf); gme_free_info(info); return 0; } #define AUDIO_PKT_SIZE 512 static int read_close_gme(AVFormatContext *s) { GMEContext *gme = s->priv_data; if (gme->music_emu) gme_delete(gme->music_emu); return 0; } static int read_header_gme(AVFormatContext *s) { AVStream *st; AVIOContext *pb = s->pb; GMEContext *gme = s->priv_data; int64_t sz = avio_size(pb); int64_t duration; char *buf; char dummy; int ret; if (sz < 0) { av_log(s, AV_LOG_WARNING, "Could not determine file size\n"); sz = gme->max_size; } else if (gme->max_size && sz > gme->max_size) { sz = gme->max_size; } buf = av_malloc(sz); if (!buf) return AVERROR(ENOMEM); sz = avio_read(pb, buf, sz); // Data left means our buffer (the max_size option) is too small if (avio_read(pb, &dummy, 1) == 1) { av_log(s, AV_LOG_ERROR, "File size is larger than max_size option " "value %"PRIi64", consider increasing the max_size option\n", gme->max_size); av_freep(&buf); return AVERROR_BUFFER_TOO_SMALL; } if (gme_open_data(buf, sz, &gme->music_emu, gme->sample_rate)) { gme->music_emu = NULL; /* Just for safety */ av_freep(&buf); return AVERROR_INVALIDDATA; } av_freep(&buf); ret = load_metadata(s, &duration); if (ret < 0) return ret; if (gme_start_track(gme->music_emu, gme->track_index)) return AVERROR_UNKNOWN; st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); avpriv_set_pts_info(st, 64, 1, 1000); if (duration > 0) st->duration = duration; st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; st->codecpar->codec_id = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE); st->codecpar->ch_layout.nb_channels = 2; st->codecpar->sample_rate = gme->sample_rate; return 0; } static int read_packet_gme(AVFormatContext *s, AVPacket *pkt) { GMEContext *gme = s->priv_data; int n_samples = AUDIO_PKT_SIZE / 2; int ret; if (gme_track_ended(gme->music_emu)) return AVERROR_EOF; if ((ret = av_new_packet(pkt, AUDIO_PKT_SIZE)) < 0) return ret; if (gme_play(gme->music_emu, n_samples, (short *)pkt->data)) return AVERROR_EXTERNAL; return 0; } static int read_seek_gme(AVFormatContext *s, int stream_idx, int64_t ts, int flags) { GMEContext *gme = s->priv_data; if (!gme_seek(gme->music_emu, (int)ts)) return AVERROR_EXTERNAL; return 0; } static int probe_gme(const AVProbeData *p) { // Reads 4 bytes - returns "" if unknown format. if (gme_identify_header(p->buf)[0]) { if (p->buf_size < 16384) return AVPROBE_SCORE_MAX / 4 ; else return AVPROBE_SCORE_MAX / 2; } return 0; } static const AVClass class_gme = { .class_name = "Game Music Emu demuxer", .option = options, .version = LIBAVUTIL_VERSION_INT, }; const AVInputFormat ff_libgme_demuxer = { .name = "libgme", .long_name = NULL_IF_CONFIG_SMALL("Game Music Emu demuxer"), .priv_data_size = sizeof(GMEContext), .flags_internal = FF_FMT_INIT_CLEANUP, .read_probe = probe_gme, .read_header = read_header_gme, .read_packet = read_packet_gme, .read_close = read_close_gme, .read_seek = read_seek_gme, .priv_class = &class_gme, };