OK, I tried doing a smooth zoom at 25% fps from a crappy YouTube video (it's the best I could find to demonstrate). Much to my consternation, I could not open it with DirectShowSource. I couldn't open it with QTSource either. It is an MP4 and has similar specs to your file:
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 11.3 MiB
Duration : 29s 790ms
Overall bit rate mode : Variable
Overall bit rate : 3 195 Kbps
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=60
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 29s 778ms
Bit rate : 3 001 Kbps
Maximum bit rate : 4 939 Kbps
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 fps
Color space : YUV
I found a very useful plugin for MPEG-2 and -4,
MpegAutoIndex, that worked. Note that
VirusTotal found 5/45 possible malware results in MpegAutoIndex.zip but they look like typical false positives. They are all from minor virus scanners, two of which almost ALWAYS show false positives.
Here's the script I used:
v = MpegAutoIndexSource("HD video by Canon SX50 camera - 50x zoom example 1.mp4")
fps = v.FrameRate()
v = v.Trim(50, 200).AssumeFPS(fps/4)
v = v.ConvertToYV12().AutoCrop(0, wMultOf=16, hMultOf=16).MSU_FRC(4, "fast")
return v
This worked beautifully. Here is a comparison of the video at 100%, 25% using just AssumeFPS, and 25% using AssumeFPS with FRC:
zoom StackHorizontal 3As always, it is much better to download this and view it properly on a real standalone player.
I tried using ConvertFPS but it was harder to use and the quality was horrible.