avformat/alp: allow seeking to start

Allows "ffplay -loop" to work.

Signed-off-by: Zane van Iperen <zane@zanevaniperen.com>
This commit is contained in:
Zane van Iperen 2021-03-22 23:12:34 +10:00
parent 3cc4a140ef
commit ea9732c5d6
No known key found for this signature in database
GPG Key ID: 68616B2D8AC4DCC5

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@ -72,38 +72,39 @@ static int alp_read_header(AVFormatContext *s)
{
int ret;
AVStream *st;
ALPHeader hdr;
ALPHeader *hdr = s->priv_data;
AVCodecParameters *par;
if ((hdr.magic = avio_rl32(s->pb)) != ALP_TAG)
if ((hdr->magic = avio_rl32(s->pb)) != ALP_TAG)
return AVERROR_INVALIDDATA;
hdr.header_size = avio_rl32(s->pb);
hdr->header_size = avio_rl32(s->pb);
if (hdr.header_size != 8 && hdr.header_size != 12) {
if (hdr->header_size != 8 && hdr->header_size != 12) {
return AVERROR_INVALIDDATA;
}
if ((ret = avio_read(s->pb, hdr.adpcm, sizeof(hdr.adpcm))) < 0)
if ((ret = avio_read(s->pb, hdr->adpcm, sizeof(hdr->adpcm))) < 0)
return ret;
else if (ret != sizeof(hdr.adpcm))
else if (ret != sizeof(hdr->adpcm))
return AVERROR(EIO);
if (strncmp("ADPCM", hdr.adpcm, sizeof(hdr.adpcm)) != 0)
if (strncmp("ADPCM", hdr->adpcm, sizeof(hdr->adpcm)) != 0)
return AVERROR_INVALIDDATA;
hdr.unk1 = avio_r8(s->pb);
hdr.num_channels = avio_r8(s->pb);
hdr->unk1 = avio_r8(s->pb);
hdr->num_channels = avio_r8(s->pb);
if (hdr.header_size == 8) {
if (hdr->header_size == 8) {
/* .TUN music file */
hdr.sample_rate = 22050;
hdr->sample_rate = 22050;
} else {
/* .PCM sound file */
hdr.sample_rate = avio_rl32(s->pb);
hdr->sample_rate = avio_rl32(s->pb);
}
if (hdr.sample_rate > 44100) {
if (hdr->sample_rate > 44100) {
avpriv_request_sample(s, "Sample Rate > 44100");
return AVERROR_PATCHWELCOME;
}
@ -115,12 +116,12 @@ static int alp_read_header(AVFormatContext *s)
par->codec_type = AVMEDIA_TYPE_AUDIO;
par->codec_id = AV_CODEC_ID_ADPCM_IMA_ALP;
par->format = AV_SAMPLE_FMT_S16;
par->sample_rate = hdr.sample_rate;
par->channels = hdr.num_channels;
par->sample_rate = hdr->sample_rate;
par->channels = hdr->num_channels;
if (hdr.num_channels == 1)
if (hdr->num_channels == 1)
par->channel_layout = AV_CH_LAYOUT_MONO;
else if (hdr.num_channels == 2)
else if (hdr->num_channels == 2)
par->channel_layout = AV_CH_LAYOUT_STEREO;
else
return AVERROR_INVALIDDATA;
@ -151,12 +152,25 @@ static int alp_read_packet(AVFormatContext *s, AVPacket *pkt)
return 0;
}
static int alp_seek(AVFormatContext *s, int stream_index,
int64_t pts, int flags)
{
const ALPHeader *hdr = s->priv_data;
if (pts != 0)
return AVERROR(EINVAL);
return avio_seek(s->pb, hdr->header_size + 8, SEEK_SET);
}
AVInputFormat ff_alp_demuxer = {
.name = "alp",
.long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
.priv_data_size = sizeof(ALPHeader),
.read_probe = alp_probe,
.read_header = alp_read_header,
.read_packet = alp_read_packet
.read_packet = alp_read_packet,
.read_seek = alp_seek,
};
#endif