avformat/cdg: add probe

This commit is contained in:
Paul B Mahol 2023-02-14 22:25:42 +01:00
parent eabc304d12
commit 097653bae6
1 changed files with 17 additions and 0 deletions

View File

@ -26,6 +26,22 @@
#define CDG_COMMAND 0x09
#define CDG_MASK 0x3F
static int read_probe(const AVProbeData *p)
{
const int cnt = p->buf_size / CDG_PACKET_SIZE;
int score = 0;
for (int i = 0; i < cnt; i++) {
const int x = p->buf[i * CDG_PACKET_SIZE] & CDG_MASK;
score += x == CDG_COMMAND;
if (x != CDG_COMMAND && x != 0)
return 0;
}
return FFMIN(score, AVPROBE_SCORE_MAX);
}
static int read_header(AVFormatContext *s)
{
AVStream *vst;
@ -70,6 +86,7 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt)
const AVInputFormat ff_cdg_demuxer = {
.name = "cdg",
.long_name = NULL_IF_CONFIG_SMALL("CD Graphics"),
.read_probe = read_probe,
.read_header = read_header,
.read_packet = read_packet,
.flags = AVFMT_GENERIC_INDEX,