From 88f038ac97a875f25c2eceac6d2107a09314984c Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Thu, 17 Jul 2014 04:25:21 +0200
Subject: [PATCH] avformat/dv: implement fallback in dv_extract_pack()
Fixes Ticket2340
Fixes Ticket2341
Based-on mail from Dave Rice <dave@dericed.com>
Tested-by: Dave Rice <dave@dericed.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
libavformat/dv.c | 43 +++++++++++++++++++++++--------------------
1 file changed, 23 insertions(+), 20 deletions(-)
diff --git a/libavformat/dv.c b/libavformat/dv.c
index 4f7b062f8bb..1e15c082035 100644
--- a/libavformat/dv.c
+++ b/libavformat/dv.c
@@ -72,30 +72,33 @@ static inline uint16_t dv_audio_12to16(uint16_t sample)
return result;
}
-/*
- * This is the dumbest implementation of all -- it simply looks at
- * a fixed offset and if pack isn't there -- fails. We might want
- * to have a fallback mechanism for complete search of missing packs.
- */
static const uint8_t *dv_extract_pack(uint8_t *frame, enum dv_pack_type t)
{
int offs;
+ int c;
- switch (t) {
- case dv_audio_source:
- offs = (80 * 6 + 80 * 16 * 3 + 3);
- break;
- case dv_audio_control:
- offs = (80 * 6 + 80 * 16 * 4 + 3);
- break;
- case dv_video_control:
- offs = (80 * 5 + 48 + 5);
- break;
- case dv_timecode:
- offs = (80*1 + 3 + 3);
- break;
- default:
- return NULL;
+ for (c = 0; c < 10; c++) {
+ switch (t) {
+ case dv_audio_source:
+ if (c&1) offs = (80 * 6 + 80 * 16 * 0 + 3 + c*12000);
+ else offs = (80 * 6 + 80 * 16 * 3 + 3 + c*12000);
+ break;
+ case dv_audio_control:
+ if (c&1) offs = (80 * 6 + 80 * 16 * 1 + 3 + c*12000);
+ else offs = (80 * 6 + 80 * 16 * 4 + 3 + c*12000);
+ break;
+ case dv_video_control:
+ if (c&1) offs = (80 * 3 + 8 + c*12000);
+ else offs = (80 * 5 + 48 + 5 + c*12000);
+ break;
+ case dv_timecode:
+ offs = (80*1 + 3 + 3);
+ break;
+ default:
+ return NULL;
+ }
+ if (frame[offs] == t)
+ break;
}
return frame[offs] == t ? &frame[offs] : NULL;
--
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