![]() ![]() So by calculating the cadence in Excel you can fairly quickly strip out the false positives as well as pick up when the cadence skips, and come up with the correct list of duplicate frames. Also, the FXscript I wrote to detect duplicate frames will trigger some false positives, especially with slow moving or still scenes. For example, a 25 fps source converted to 29.97 fps will not simply have every 5th frame duplicated - eventually the sequence will spit out 9 unique frames before duplication restarts. I then cut-and-paste the output of the Console into Text Wrangler to grep out the frame numbers (since the Console also spits out extraneous text) and past that into Excel.Īt this point some manual checking is required since the cadence of the duplicated frames may not be constant if the clip is more than a minute long. I developed my own method of doing this - it's partly-automated, clunky and not for the faint hearted - but much better than doing it manually on any clip more than a few seconds long.įirst, I wrote an FXscript in FCP to detect duplicate frames and output the frame number of each duplicate to the Mac Console using the FXscript debug command. I am not aware of any app that will do this automatically, and certainly not without re-encoding, since just about every video format known to man uses some form of temporal compression hence to manipulate individual frames requires re-encoding. * Compressor "interlace" control works with progressive clips. Results vary somewhat.įPCX does this more conveniently when adding nonconforming clips to the timeline, but may not be faster, especially for Optical Blends. Or: For a less precise, but far faster method, use Frame Blending instead -Ĭompressor > Rate Conversion > Best. This is a slow process that eats available ram, but definitely produces the best results. Return the shortened to the original speed using Apple Motion with Optical Blending set at 83.33%, 80%, etc.** When conforming up to higher rate, the resulting clip will be shorter and, hence, faster. Open the resulting clip in Cinema Tools and conform to 30, 29.97 etc. Set Compressor frame controls to interlace > reverse telecine*, duration > 100%.Ģ. To fix this when converting to a higher frame rate -ġ. I've run into a variety of odd frame rate issues working with archival files. Note: sometimes the duplicate frames are not regular over the length of a movie due to multiple edit patches from previous files. It is critical that the clip start at the beginning (frame 1) of this sequence -įor example: 1 2 3 4 4 1 2 3. For instance, does anyone know if a script / method exists for MPEGStreamclip (which doesn't reencode) to do this? ![]() No, the idea is to input a file in an app or utility, tell the program to delete every nth frame, rejoin without reeconding. Apps like Loosless Frame Rate Converter (free) may work when no duplicate frames are found, that is, when a 24fps movie, for example, has been converted to 25fps just by speeding it up by 4% (I also hate that).Extremely time-consuming for long files, and the video may lose quality. ![]()
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