From eb8de45c3c55721f0fc02cefcf1d08980b7ab67d Mon Sep 17 00:00:00 2001 From: Aurelien Jacobs Date: Mon, 13 Jun 2011 18:30:55 +0200 Subject: [PATCH] nsv: simplify probe function --- libavformat/nsvdec.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/libavformat/nsvdec.c b/libavformat/nsvdec.c index 81c672e388..4898187f3a 100644 --- a/libavformat/nsvdec.c +++ b/libavformat/nsvdec.c @@ -21,6 +21,7 @@ #include "avformat.h" #include "riff.h" #include "libavutil/dict.h" +#include "libavutil/intreadwrite.h" //#define DEBUG_DUMP_INDEX // XXX dumbdriving-271.nsv breaks with it commented!! #define CHECK_SUBSEQUENT_NSVS @@ -736,10 +737,8 @@ static int nsv_read_close(AVFormatContext *s) static int nsv_probe(AVProbeData *p) { - int i; - int score; - int vsize, asize, auxcount; - score = 0; + int i, score = 0; + av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size); /* check file header */ /* streamed files might not have any header */ @@ -751,19 +750,14 @@ static int nsv_probe(AVProbeData *p) /* seems the servers don't bother starting clean chunks... */ /* sometimes even the first header is at 9KB or something :^) */ for (i = 1; i < p->buf_size - 3; i++) { - if (p->buf[i+0] == 'N' && p->buf[i+1] == 'S' && - p->buf[i+2] == 'V' && p->buf[i+3] == 's') { - score = AVPROBE_SCORE_MAX/5; + if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) { /* Get the chunk size and check if at the end we are getting 0xBEEF */ - auxcount = p->buf[i+19]; - vsize = p->buf[i+20] | p->buf[i+21] << 8; - asize = p->buf[i+22] | p->buf[i+23] << 8; - vsize = (vsize << 4) | (auxcount >> 4); - if ((asize + vsize + i + 23) < p->buf_size - 2) { - if (p->buf[i+23+asize+vsize+1] == 0xEF && - p->buf[i+23+asize+vsize+2] == 0xBE) - return AVPROBE_SCORE_MAX-20; - } + int vsize = AV_RL24(p->buf+i+19) >> 4; + int asize = AV_RL16(p->buf+i+22); + int offset = i + 23 + asize + vsize + 1; + if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF) + return 4*AVPROBE_SCORE_MAX/5; + score = AVPROBE_SCORE_MAX/5; } } /* so we'll have more luck on extension... */