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  1. I'm currently working on a review where I need to accurately time things on my computer. Instead of a stopwatch, I recorded the screen with my digital camera. I then load the video in AviDemux to look for the frame #s of the start and end points, subtract the two to get the # of frames it took and divided this by 30 to get the time it took.

    This method worked great with my last digital camera that recorded video files using the MJPEG video codec at 30FPS and meant that my timings were accurate to 1/30th of a second.

    I've since got a new shiny Panasonic DMC-ZS7 which records in the AVCLite format by default as MTS files and made quite a lot of recordings. Now I've run into a problem. While AviDemux 2.5.3 can open the MTS files, the seek slider does not work, so I need to hold down the right arrow key to navigate. This is a painfully time consuming process, which can take several minutes to reach the desired points. Also, if I touch or try to drag the slider, it jumps back to the first frame.

    So far I have spent several hours now trying to find any video player (or editor) that can display an MTS file frame by frame. While there are plenty of players and utilities that do this for MPEG2 TS files, I haven't come across anything that lets me accurately view an MTS file frame by frame. Media Player Classic was as close as I got that can seek, but it only displays the current time value as a full second and has problems navigating frame by frame in reverse.

    I would really appreciate if anyone can let me know of any freely available utility, player, editor, etc. that can show an MTS file frame by frame showing current frame # or timestamp (to 1/100th second), i.e. something similar to AviDemux.
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  2. avchd lite is problematic , because it has a frame repeat flag that many programs cannot handle properly
    one way is to use avisynth and ffmpegsource2 , and navigate using the avs script in avsp or vdub

    1) install avisynth

    2) download ffms plugin, unzip & place contents in avisynth\plugins folder (especiall the .dll and .avsi)
    http://code.google.com/p/ffmpegsource/

    3) open a text file in notepad in the same directory as the video, copy the following (changing filename to match), save, then rename extension .txt to .avs

    ffmpegsource2("video.mts", atrack=-1)
    info()

    4) open that in vdub or avsp to navigate fwd/bwd frame by frame, the frame number and timecode will be displayed at the top left corner. You can also use a media player to open .avs files (e.g. mpc) , but navigation won't be as good as if you had used avsp or vdub
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  3. I can confirm this works, as I can see the frame # and navigate frame by frame in both directions.

    The only issue is that seeking is slow at roughly 15 seconds per 1 minute of video, likely due to the frame serving process. For example, if I drag the navigation bar to 2 minutes in VirtualDub or AvsPmod, it takes 30 seconds to update the picture. On the other hand, this is still a lot quicker than AviDemux where I could only navigate forward at slower than playback speed.

    At least I'll get by with this method and must remember to set my camera to MJPEG the next time I do recordings.

    Thank you very much for your help and for the quick reply.
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  4. Hmm , not sure why there is such a lag. The 1st time you use it, it might take a few seconds or a minute (depending on length of clip) to index the file. Subsequent seeks should be much faster. The index is necessary for frame accuracy. If you recall scrubbing with media player you might lose location and/or the time codes might be incorrect - that's because the media player is using directshow and it isn't necessarily frame accurate.

    If you use the ffms-mt (multithreaded) version, it should be faster on the decoding aspect. There is a beta download on the same page. However, it still needs to generate index (so that first time you open it will still take the same amount of extra time to generate index)
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  5. I'm not sure why there is a lag either since if I load a regular AVI file in VirtualDub, seeking is instant.

    I didn't notice the multi-threaded version until you mentioned. That makes a huge difference now, as the seek time is now 5 seconds per 1 minute of video.

    Most of my clips are around 5 to 10 minutes and as I need to navigate some clips several seconds at a time to watch the progress, this works out almost as quick as navigating through MJPEG files.

    Thanks again for your help.
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  6. After going through many of my MTS recordings, I came across some that threw up this avisynth error in VirtualDub when I tried navigating in reverse:

    FFmpegSource: Frame accurate seeking is not possible in this file
    I did a bit of research into this error and it turns out that this is related to the Haali Media Splitter. So for curiosity, I downloaded and installed the latest version of Haali Media Splitter and this fixed the reverse navigation issue.

    I just wanted to mention this in case anyone else encountered this issue and wondered how to correct it.
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