| 1 | /* |
| 2 | * This file is part of FFmpeg. |
| 3 | * |
| 4 | * FFmpeg is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * FFmpeg 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 GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with FFmpeg; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | /** |
| 20 | * @file |
| 21 | * libgme demuxer |
| 22 | */ |
| 23 | |
| 24 | #include <gme/gme.h> |
| 25 | #include "libavutil/avstring.h" |
| 26 | #include "libavutil/eval.h" |
| 27 | #include "libavutil/opt.h" |
| 28 | #include "avformat.h" |
| 29 | #include "internal.h" |
| 30 | |
| 31 | typedef struct GMEContext { |
| 32 | const AVClass *class; |
| 33 | Music_Emu *music_emu; |
| 34 | gme_info_t *info; ///< selected track |
| 35 | |
| 36 | /* options */ |
| 37 | int track_index; |
| 38 | int sample_rate; |
| 39 | int64_t max_size; |
| 40 | } GMEContext; |
| 41 | |
| 42 | #define OFFSET(x) offsetof(GMEContext, x) |
| 43 | #define A AV_OPT_FLAG_AUDIO_PARAM |
| 44 | #define D AV_OPT_FLAG_DECODING_PARAM |
| 45 | static const AVOption options[] = { |
| 46 | {"track_index", "set track that should be played", OFFSET(track_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, A|D}, |
| 47 | {"sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 44100}, 1000, 999999, A|D}, |
| 48 | {"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}, |
| 49 | {NULL} |
| 50 | }; |
| 51 | |
| 52 | static void add_meta(AVFormatContext *s, const char *name, const char *value) |
| 53 | { |
| 54 | if (value && value[0]) |
| 55 | av_dict_set(&s->metadata, name, value, 0); |
| 56 | } |
| 57 | |
| 58 | static int load_metadata(AVFormatContext *s) |
| 59 | { |
| 60 | GMEContext *gme = s->priv_data; |
| 61 | gme_info_t *info = gme->info; |
| 62 | char buf[30]; |
| 63 | |
| 64 | add_meta(s, "system", info->system); |
| 65 | add_meta(s, "game", info->game); |
| 66 | add_meta(s, "song", info->song); |
| 67 | add_meta(s, "author", info->author); |
| 68 | add_meta(s, "copyright", info->copyright); |
| 69 | add_meta(s, "comment", info->comment); |
| 70 | add_meta(s, "dumper", info->dumper); |
| 71 | |
| 72 | snprintf(buf, sizeof(buf), "%d", (int)gme_track_count(gme->music_emu)); |
| 73 | add_meta(s, "tracks", buf); |
| 74 | |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | #define AUDIO_PKT_SIZE 512 |
| 79 | |
| 80 | static int read_header_gme(AVFormatContext *s) |
| 81 | { |
| 82 | AVStream *st; |
| 83 | AVIOContext *pb = s->pb; |
| 84 | GMEContext *gme = s->priv_data; |
| 85 | int64_t sz = avio_size(pb); |
| 86 | char *buf; |
| 87 | char dummy; |
| 88 | |
| 89 | if (sz < 0) { |
| 90 | av_log(s, AV_LOG_WARNING, "Could not determine file size\n"); |
| 91 | sz = gme->max_size; |
| 92 | } else if (gme->max_size && sz > gme->max_size) { |
| 93 | sz = gme->max_size; |
| 94 | } |
| 95 | |
| 96 | buf = av_malloc(sz); |
| 97 | if (!buf) |
| 98 | return AVERROR(ENOMEM); |
| 99 | sz = avio_read(pb, buf, sz); |
| 100 | |
| 101 | // Data left means our buffer (the max_size option) is too small |
| 102 | if (avio_read(pb, &dummy, 1) == 1) { |
| 103 | av_log(s, AV_LOG_ERROR, "File size is larger than max_size option " |
| 104 | "value %"PRIi64", consider increasing the max_size option\n", |
| 105 | gme->max_size); |
| 106 | return AVERROR_BUFFER_TOO_SMALL; |
| 107 | } |
| 108 | |
| 109 | if (gme_open_data(buf, sz, &gme->music_emu, gme->sample_rate)) { |
| 110 | av_freep(&buf); |
| 111 | return AVERROR_INVALIDDATA; |
| 112 | } |
| 113 | av_freep(&buf); |
| 114 | |
| 115 | if (gme_track_info(gme->music_emu, &gme->info, gme->track_index)) |
| 116 | return AVERROR_STREAM_NOT_FOUND; |
| 117 | |
| 118 | if (gme_start_track(gme->music_emu, gme->track_index)) |
| 119 | return AVERROR_UNKNOWN; |
| 120 | |
| 121 | load_metadata(s); |
| 122 | |
| 123 | st = avformat_new_stream(s, NULL); |
| 124 | if (!st) |
| 125 | return AVERROR(ENOMEM); |
| 126 | avpriv_set_pts_info(st, 64, 1, 1000); |
| 127 | if (st->duration > 0) |
| 128 | st->duration = gme->info->length; |
| 129 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 130 | st->codec->codec_id = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE); |
| 131 | st->codec->channels = 2; |
| 132 | st->codec->sample_rate = gme->sample_rate; |
| 133 | |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | static int read_packet_gme(AVFormatContext *s, AVPacket *pkt) |
| 138 | { |
| 139 | GMEContext *gme = s->priv_data; |
| 140 | int n_samples = AUDIO_PKT_SIZE / 2; |
| 141 | int ret; |
| 142 | |
| 143 | if (gme_track_ended(gme->music_emu)) |
| 144 | return AVERROR_EOF; |
| 145 | |
| 146 | if ((ret = av_new_packet(pkt, AUDIO_PKT_SIZE)) < 0) |
| 147 | return ret; |
| 148 | |
| 149 | if (gme_play(gme->music_emu, n_samples, (short *)pkt->data)) |
| 150 | return AVERROR_EXTERNAL; |
| 151 | pkt->size = AUDIO_PKT_SIZE; |
| 152 | |
| 153 | return 0; |
| 154 | } |
| 155 | |
| 156 | static int read_close_gme(AVFormatContext *s) |
| 157 | { |
| 158 | GMEContext *gme = s->priv_data; |
| 159 | gme_free_info(gme->info); |
| 160 | gme_delete(gme->music_emu); |
| 161 | return 0; |
| 162 | } |
| 163 | |
| 164 | static int read_seek_gme(AVFormatContext *s, int stream_idx, int64_t ts, int flags) |
| 165 | { |
| 166 | GMEContext *gme = s->priv_data; |
| 167 | if (!gme_seek(gme->music_emu, (int)ts)) |
| 168 | return AVERROR_EXTERNAL; |
| 169 | return 0; |
| 170 | } |
| 171 | |
| 172 | static int probe_gme(AVProbeData *p) |
| 173 | { |
| 174 | // Reads 4 bytes - returns "" if unknown format. |
| 175 | if (gme_identify_header(p->buf)[0]) { |
| 176 | if (p->buf_size < 16384) |
| 177 | return AVPROBE_SCORE_MAX / 4 ; |
| 178 | else |
| 179 | return AVPROBE_SCORE_MAX / 2; |
| 180 | } |
| 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | static const AVClass class_gme = { |
| 185 | .class_name = "Game Music Emu demuxer", |
| 186 | .item_name = av_default_item_name, |
| 187 | .option = options, |
| 188 | .version = LIBAVUTIL_VERSION_INT, |
| 189 | }; |
| 190 | |
| 191 | AVInputFormat ff_libgme_demuxer = { |
| 192 | .name = "libgme", |
| 193 | .long_name = NULL_IF_CONFIG_SMALL("Game Music Emu demuxer"), |
| 194 | .priv_data_size = sizeof(GMEContext), |
| 195 | .read_probe = probe_gme, |
| 196 | .read_header = read_header_gme, |
| 197 | .read_packet = read_packet_gme, |
| 198 | .read_close = read_close_gme, |
| 199 | .read_seek = read_seek_gme, |
| 200 | .priv_class = &class_gme, |
| 201 | }; |