From b0cd65c70465da729d950dfff1c20129e81462fc Mon Sep 17 00:00:00 2001
From: Paul B Mahol <onemda@gmail.com>
Date: Tue, 14 Feb 2023 22:25:42 +0100
Subject: [PATCH] avformat/cdg: add probe
Signed-off-by: Paul B Mahol <onemda@gmail.com>
---
libavformat/cdg.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
@@ -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,
--
2.39.1