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I have many JPEGs captured as part of different timelapses. I have all of them stored as they came from the camera, but it is starting to take up a lot of space.

I want to keep the photos at their original size so that I can do things like crop/pan/scale/re-sample for the time lapse at a later stage.

What is a better way of storing them without losing quality?

  • Without any information on the photo format used (RAW, JPEG ?) or the final goal, it's very hard to give any usable advice. Can you give more details : picture's format, original size and minimum size needed,... – Olivier Aug 6 '15 at 16:33
  • Sorry, camera is not capable of RAW. I was hoping someone already had experience and would suggest something like "encode it to a video file using XX format". I'll investigate that and see if I can both save space and retain quality. – dirk Aug 7 '15 at 16:27
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If you are looking to reduce space, you are going to lose quality in some manner. If you strip the exif data, you will not lose image quality, but can (marginally) reduce the size of the files at the expense of that information.

If you are looking for more significant reductions, I would suggest looking at tools that reduce file size by maintaining apparent visual quality. There are paid (e.g. JPEGMini) and free (e.g. Jpeg-archive or CompressJpeg) tools that can achieve this. Realistically, if you are combining these into a timelapse, I don't think this re-compression is going to be an issue. If you are planning on using the images to print at large sizes, then you are better off just buying extra hard drives.

  • Further compressing the jpeg, to what is apparently the same, will lead to scintillating in the movie. – JDługosz Aug 8 '15 at 5:28
  • Thanks, I was hoping that lossless compression across video frames would possible save some space, but I guess I was too optimistic :) – dirk Sep 2 '15 at 17:50
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By "unprocessed" you mean not turned into the movie yet? Or nothing that requires manual attention and interaction?

If you will be cropping, crop the stills early.

The video (if normal video usage; you did not specify) is much lower resolution than a photo. So resuce the resolution to the final dimentions, right away.

You say these are in-camera jpeg files, so they are already small. Get another hdd, valuing price over performance. Last week they were running $30/Terabyte.

  • You could start forming the movie before you hace all the shots. Each group, say 1 seconds worth, can be formed into a video. Then, paste them together.

Note that anything you do might result in lost quality unless you are very careful and know what you are doing. You will also lose flexibility; e.g. you might wish to reframe once you are editing.

For real savings, making each run of 24 frames (or whatever) into a movie right away is the only real approach. If you finish it the waynthe movie will be, you are no worse off since you are not saving intermediate forms. And really, you need the space for the finished movie anyway!

If each run corresponds to a "group-of-pictures" in the final video encoding, and you find the right tool you can concatenate them together without any re-encoding (which would be generational loss).


Really though, if an in-camera jpeg is 5Mb it would take 200,000 images to fill a terabyte, which would be enough to make a 55-hour movie. So can you detail just what your space issues are?

  • I don't think I understand the advice on grouping every 1 second worth of photos into a video, why wouldn't I simply make all of the photos a video that I can work with later? Would that imply less of a space saving or more quality loss? – dirk Aug 11 '15 at 12:37
  • A 1-second video is much smaller than 24 photos. You are compressing and reducing the resolution, but to the final end result somthere is not going to be generational loss. A group-of-pictures in H.264 encoding uses the similarity among frames, not just one frame at a time, so it's more compact. – JDługosz Aug 11 '15 at 18:49
  • Re make all the photos into a video: if you hace them all, you are done. I was thinking of how to reduce storage while you are still collecting material. Did I miss the question? – JDługosz Aug 11 '15 at 18:51
  • I actually just did a test and encoding a file loss less with h264 results in a video file that takes up more space. I'll think I'll just keep the images. – dirk Sep 2 '15 at 17:48
  • Probably noise in the images; but still I would expect a group compressed with interframe comparisons to be no larger than just compressing each frame. Lossless means that the same block on two frames will never match exactly. IAC, keeping the originals is best. – JDługosz Sep 2 '15 at 18:35
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Time lapse implies it will be made into movies, which HD is about 2 megapixels each frame. If so, and if you took these with a 12 or 24 megapixel camera, then for smaller storage, you could (crop and) batch resample them to 1920x1080 pixels now, instead of waiting until later to do the same. This of course implies that you do some of the work now.

  • That's easy and straightforward. But the reduced stills need to be stored with very low compression so they don't degrade when re-encoding the video. I expect each still would be 1.5MB. – JDługosz Aug 11 '15 at 18:55
  • That should be greatly smaller than it is now. Don't know which camera, but 2 megapixels for HD video is 2/12 the size of 12 megapixels, or 2/24 the size of 24 megapixels. That is significantly smaller. At any compression ratio (assuming same as the original file) that will be a greatly smaller file (because 1920x1080 is only 2 megapixels). And (assuming you also did all the crop you might need to do), the 2 megapixels is still very compatible size with your HD movie goal. 1920x1080 is only 5.9 MB if totally uncompressed. 5:1 high compression = 1.1 MB file size. How big is it now? :) – WayneF Aug 11 '15 at 23:28
  • My 4:1 compression for jpeg at no quantization is based on files in the 2 to 3 megapixel range, which was current for cameras when I did the experiments. High res images (20 MP) will compress at a higher ratio without real loss because there will be more gradual changing from one pixel to another. It depends on the limiting sharpness of the camera in all its details, too. – JDługosz Aug 12 '15 at 1:57
  • But it's been a long time sincd I worried about having enough space for my pictures. In 1999 I realized that disk space was increasing faster than camera resolution, and figured I could keep everything on a mounted drive rather than off-line disks or other removable media. – JDługosz Aug 12 '15 at 2:01

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