ffmpeg getProperty CV_CAP_PROP_POS_MSEC incorrect + fix (Bug #91)

Added by amit man about 15 years ago. Updated over 12 years ago.

Status:	Done	Start date:
Priority:	High	Due date:
Assignee:	-	% Done:	0%
Category:	highgui-video
Target version:	-
Affected version:		Operating System:
Difficulty:		HW Platform:
Pull request:

Description

in cvcap_ffmpeg line 622-625:

case CV_CAP_PROP_POS_MSEC:
if(video_st->cur_dts != AV_NOPTS_VALUE_)
return (((double)video_st->cur_dts-1) *1000) / av_q2d (video_st->r_frame_rate);
break;

should be:

case CV_CAP_PROP_POS_MSEC:
        if(video_st->cur_dts != AV_NOPTS_VALUE_) {
            return (((double)video_st->cur_dts-1) *1000.0f * av_q2d (video_st->time_base));
        }       
        break;

i.e use ffmpeg time_base and not r_frame_rate as the base frame rate. applying this fix give the correct results for some file formats (such as flv) when before it did not