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<DIV><FONT color=#000000 size=3 face=宋体>You can get frame rate
as follow:</FONT></DIV>
<DIV>AVStream *st = pFormatCtx->streams[your_video_index];</DIV>
<DIV>double frame_rate = st->r_frame_rate.num /
(double)st->r_frame_rate.den;</DIV>
<DIV> </DIV>
<DIV align=left><FONT color=#c0c0c0 size=2 face=Verdana>2013-05-22</FONT></DIV>
<DIV align=left><FONT size=2 face=Verdana>
<HR style="WIDTH: 122px; HEIGHT: 2px" id=SignNameHR align=left SIZE=2>
</FONT></DIV>
<DIV align=left><FONT color=#c0c0c0 size=2 face=Verdana><SPAN
id=_FlashSignName>Guohui Huang</SPAN></FONT></DIV>
<DIV><FONT size=2 face=Verdana>
<HR>
</FONT></DIV>
<DIV><FONT size=2 face=Verdana><STRONG>发件人：</STRONG>Taha Ansari
<mtaha.ansari@gmail.com></FONT></DIV>
<DIV><FONT size=2
face=Verdana><STRONG>发送时间：</STRONG>2013-05-21 23:04</FONT></DIV>
<DIV><FONT size=2 face=Verdana><STRONG>主题：</STRONG>[Libav-user] Reading correct
frame rate (fps) of input video</FONT></DIV>
<DIV><FONT size=2 face=Verdana><STRONG>收件人：</STRONG>"This list is about using
libavcodec, libavformat, libavutil, libavdevice and
libavfilter."<libav-user@ffmpeg.org></FONT></DIV>
<DIV><FONT size=2 face=Verdana><STRONG>抄送：</STRONG></FONT></DIV>
<DIV><FONT size=2 face=Verdana></FONT> </DIV>
<DIV><FONT size=2 face=Verdana>
<DIV dir=ltr>Hi!<BR><BR>I am trying to read exact values for frame rate (fps)
from any input video file. I have been trying to debug different structures like
AVFormatCtx, etc. but cannot seem to figure it out. For a test case, here is the
code I have managed (just the source snippet, include files etc. are all
understandable):<BR><BR>//---------------------------------------------------------------------------------------------------------------------------------------------------<BR>
// ++ test code begins ++//<BR> av_register_all();<BR>
avcodec_register_all();<BR>
avformat_network_init();<BR> avdevice_register_all();<BR>
AVFormatContext *pFormatCtx = NULL;<BR> pFormatCtx =
avformat_alloc_context();<BR> string finalInputName =
"test_input.3gp";<BR> avformat_open_input(&pFormatCtx,
finalInputName.c_str(), NULL, NULL);<BR> if ( pFormatCtx == NULL
||<BR>
pFormatCtx->iformat == NULL )<BR> {<BR>
return -1;<BR> }<BR> // Retrieve
stream information<BR> if(avformat_find_stream_info(pFormatCtx,
NULL)<0)<BR> return -1; // Couldn't find stream
information<BR><BR> // Dump information about file onto standard
error<BR> av_dump_format(pFormatCtx, 0, finalInputName.c_str(),
0);<BR> // -- test code ends
--//<BR>//---------------------------------------------------------------------------------------------------------------------------------------------------<BR><BR>The
output it gives me is (in debug
console):<BR><BR>//---------------------------------------------------------------------------------------------------------------------------------------------------<BR>Input
#0, mov,mp4,m4a,3gp,3g2,mj2, from 'test_input.3gp':<BR>
Metadata:<BR> major_brand : 3gp4<BR>
minor_version : 0<BR> compatible_brands: isom3gp4<BR>
creation_time : 2013-05-20 11:54:39<BR> Duration:
00:00:23.77, start: 0.000000, bitrate: 5882 kb/s<BR> Stream
#0:0(eng): Video: mpeg4 (Advanced Simple Profile) (mp4v / 0x7634706D)<BR>,
yuv420p, 640x480 [SAR 1:1 DAR 4:3], 5752 kb/s, 30.08 fps, 30.08 tbr, 90k
tbn,<BR>300 tbc<BR> Metadata:<BR> creation_time
: 2013-05-20 11:54:39<BR> handler_name :
VideoHandle<BR> Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D),
16000 Hz, stereo, s16, 127<BR> kb/s<BR> Metadata:<BR>
creation_time : 2013-05-20 11:54:39<BR>
handler_name :
SoundHandle<BR>//---------------------------------------------------------------------------------------------------------------------------------------------------<BR><BR>Like
in above example, I can read that video is recorded at 30.08 fps, question is:
it is apparently very simple for FFmpeg to figure this out, but how can I use
this information from my own program? I was trying to follow code from FFmpeg
source file (utils.c): [void av_dump_format(AVFormatContext *ic, int
index, const char *url, int is_output)], but was easily lost there.<BR><BR>Can
anyone kindly guide me how to intercept this problem?<BR><BR>Thanks in advance
for your time...</DIV></FONT></DIV></BODY></HTML>