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Microstock Footage Forum => Video Equipment / Sofware / Technique => Topic started by: S. on April 14, 2017, 17:44

Title: Encoding Photo JPEG and file size increased by 3x?
Post by: S. on April 14, 2017, 17:44
I'm shooting some videos with an Olympus OM-d E-M5 Mk II, with the best possible quality.

For each video I cut the parts I don't need and I encode it with Photo JPEG, but the result is a lot bigger than the original file...

For example:
Original file: 21 seconds - 191 MB
Exported file: 21 seconds - 464 MB

Am I doing something wrong?
Is there a lossless way to decrease the exported file size?
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: steheap on April 14, 2017, 18:33
Nope - that sounds right to me. Your original file will probably be encoded with H264 which is much better at reducing file size. With PhotoJpeg, there is much less compression (and presumably artifacts) although there is a long thread somewhere about that!

You could reduce the quality setting of your PhotoJpegs a bit - I use 85 which seems to be acceptable at all the main agencies.

Steve
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: S. on April 14, 2017, 19:07
But how can the exported file be "better" than the original which is already compressed?
Where all this new information is coming from to justify the file size?

I already set the Photo JPEG quality to 90, I'll try with 85
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: steheap on April 14, 2017, 19:15
Remember that you have decoded the video stream to get it into your editing software (assuming you aren't just directly clipping the start and end points which might not need any re-coding). So you have already got rid of the H264 codec at that point. If you ever try to save the file directly from your editing program as an uncompressed file, you will see that it is many times as large as you are currently seeing. So you need to choose a codec to compress it again for uploading and many agencies seem to prefer PhotoJpeg that ends up with a larger file size than H264. So the comparison you need to make is whether your PhotoJpeg file is "better" than a file that uses H264 for the final output. The agencies seem to think so.

Hope that is clearer.

Steve
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: SpaceStockFootage on April 14, 2017, 20:49
There may be an option to trim the clip in-camera, which I'm assuming would keep it in the same format without re-encoding. I could be wrong. Not quite the same as editing in a professional setup, but if it doesn't need any colour correction and doesn't need to be frame perfect, then that could be an option. 
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: increasingdifficulty on April 15, 2017, 01:28
I'm shooting some videos with an Olympus OM-d E-M5 Mk II, with the best possible quality.

For each video I cut the parts I don't need and I encode it with Photo JPEG, but the result is a lot bigger than the original file...

For example:
Original file: 21 seconds - 191 MB
Exported file: 21 seconds - 464 MB

Am I doing something wrong?
Is there a lossless way to decrease the exported file size?

QuickTime, for example, lets you cut files without re-encoding. I would, however, recommend basic (color/contrast/exposure) editing to heavy editing so the clips look their best. As soon as you do that, you need to re-encode, and it's best to do that with a higher bitrate than the original to keep the quality.

Even though it's nice to have raw material as an editor, the vast majority of best-selling clips I've seen are quite heavily edited/graded.
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: billbell1960 on April 15, 2017, 19:15
This is an age old debate, but you can't improve the quality of the clip by re-encoding it as a Photo JPEG. I don't know what editor your processing your clips with, but I would suggest you look for solutions that use the native file format i.e. H264, and take care to setup the output bitrate settings to something comparable to the original file. This could be something between 75 and 100 Mbps at a variable bitrate.
You will find arguments to justify Photo JPEG for stock but in my experience, having uploaded both formats, for the time being H264 is the least problematic. 
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: increasingdifficulty on April 16, 2017, 03:26
This is an age old debate, but you can't improve the quality of the clip by re-encoding it as a Photo JPEG. I don't know what editor your processing your clips with, but I would suggest you look for solutions that use the native file format i.e. H264, and take care to setup the output bitrate settings to something comparable to the original file. This could be something between 75 and 100 Mbps at a variable bitrate.
You will find arguments to justify Photo JPEG for stock but in my experience, having uploaded both formats, for the time being H264 is the least problematic.

As soon as you make a change (color/contrast/exposure etc.) you're essentially unpacking and need to encode again. A higher bitrate than the original can then indeed mean better quality. That is, not better than the original, untouched file, but better quality than encoding with the same settings as the original.

Especially with heavy compression like h264.
Title: Re: Encoding Photo JPEG and file size increased by 3x?
Post by: SpaceStockFootage on April 16, 2017, 08:30
Agreed, but you don't even need to make a change. Just bring it into your editing software and you're needing to recode again when you export, no matter what you do to it. Doesn't matter if it's trimming a second off, coloring or something more advanced.