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I've got 14 PNG images (here but not important) that I want to put into a 2 minute loop at 15 fps.

Photoshop CS3 seemed the best tool for this so I opened them as an image sequence* and did File -> Export -> Render Video and exported as an AVI.

However I only had 14 images so I used a script (here but not important) to duplicate them as 1805 images (approx. 2 minutes of video).

When I repeated the Photoshop steps, the resulting file size was 55 MB as opposed to the original 429 KB.

All the video actually needs is the first 14 files to link to and then repeat (lossless).

What codec can I use which will do this? How do I use that codec? (I'm on OS X Lion).

I need it as a video, not a GIF.

*(Open -> first file -> tick image sequence)

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Do you need it to be fully lossles? or a video with very good quality where the loss cannot be seen by the normal human eye good enough? – d33pika Jan 21 '13 at 9:53
Also what is the size of the images? Why do you expect it to be 429KB? – d33pika Jan 21 '13 at 9:54
@d33pika 429 KB was the size when I exported just the first 14 images as AVI. It doesn't need to be good quality at all, it's just an animated GIF. I was suggesting lossless because it only needs the first 14 images, and the rest are the same. – gadgetmo Jan 21 '13 at 15:39
@d33pika compressed the 55mb file as zip with highest compression option, it got it down to 44mb. I tried 7zip and it got it down to 327KB. – gadgetmo Jan 21 '13 at 15:42

Lossless compression means there is no loss when image/video/data is compressed, Example: zip/gzip. It does not mean repeating files. To create a video out of images using ffmpeg follow commands in this link :

On Mac OS X you can install ffmpeg by following these steps:

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If you're putting a video on the web, you can use HTML5's video loop attribute:

e.g., which loops a short x264-encoded slo-mo clip from the musical Working.

See also Convert video to apng/png?

AFAICT, there are no video container formats (e.g. mp4, mkv, avi, nut, ogm) that ffmpeg supports which have a loop count in the container metadata. So you're right, you'd have to feed the repeating sequence of input frames to a video codec, and hope the encoder can find the massive redundancy.

You can call gif, mng, and webp video formats, since you can store any sequence of frames in them. None of those container formats support anything except the single still-image codec they were designed for, though. They all support animations with looping, probably all with a non-infinite loop count that would give you the 2 minutes you want.

ffmpeg -framerate 15 -loop 1 -i src/b93-'%d.png' -frames 1805 -preset veryslow -crf 23 -movflags +faststart party.mp4
2.5M    party.mp4  # see [1] for the encode log

ffmpeg -framerate 15 -i src/b93-'%d.png' -loop 128 containerloop.gif
684K    containerloop.gif
172K    containerloop.webp

ffplay can't play back animated webp, so use vwebp, or google chrome.

I have no idea why you would want this. If you have an animated gif, just play it. ffplay -ignore_loop 0 containerloop.gif will loop for 2 mins (since I made the gif with a finite loop count).

If you're making clips for a video editting project, I guess that makes sense.

[1] x264 with 16 ref frames, max of 8 b frames, fed yuv444 version of the input.

frame= 1805 fps=7.2 q=-1.0 Lsize=    2540kB time=00:02:00.20 bitrate= 173.1kbits/s    
video:2518kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.872666%
[libx264 @ 0x1a787e0] frame I:8     Avg QP:21.35  size: 18650
[libx264 @ 0x1a787e0] frame P:515   Avg QP:16.45  size:  1044
[libx264 @ 0x1a787e0] frame B:1282  Avg QP:25.79  size:  1475
[libx264 @ 0x1a787e0] consecutive B-frames:  0.7% 13.9%  0.8% 84.2%  0.0%  0.0%  0.0%  0.4%  0.0%
[libx264 @ 0x1a787e0] mb I  I16..4:  3.4% 64.4% 32.2%
[libx264 @ 0x1a787e0] mb P  I16..4:  0.9% 15.9%  0.9%  P16..4: 80.9%  0.3%  0.6%  0.0%  0.0%    skip: 0.5%
[libx264 @ 0x1a787e0] mb B  I16..4:  0.3%  2.8%  0.5%  B16..8:  4.8%  3.3%  1.9%  direct: 1.2%  skip:85.2%  L0:35.1% L1:64.0% BI: 0.9%
[libx264 @ 0x1a787e0] Weighted P-Frames: Y:75.0% UV:75.0%
[libx264 @ 0x1a787e0] ref P L0:  1.3%  0.1%  0.7%  0.1%  0.3%  0.0% 24.1% 41.7% 27.4%  0.1%  0.0%  0.0%  0.0%  0.4%  3.5%  0.4%
[libx264 @ 0x1a787e0] ref B L0:  8.7%  1.6%  0.8%  0.1%  0.7%  1.2% 74.6%  2.1%  0.0%  0.1%  0.0%  0.0%  0.4%  9.5%
[libx264 @ 0x1a787e0] ref B L1: 99.5%  0.5%
[libx264 @ 0x1a787e0] kb/s:171.40

Note the average P frame size being smaller than the average B frame.

x264 in lossless mode, rgb or yuv, didn't manage to keep its 16 reference frames lined up in a way that let it keep referencing them without re-encoding them. IDK enough about decoder picture ordering and exactly which frames get kept as references to understand why.

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