Tweet
quantize 16-bit PNG or TIFF to 10-bit, 12-bit, or 14-bit PNG to save space on an IS?
I had an idea the other day&*8230;
So, let's say we have all these 16-bit TIFFs for an Image / Frame Sequence, but we know that this is the final master, color grading is done, and so anything over 10, 12, or 14 bits will be a waste of space, right? So why not have an option to quantize those final 16-bit-per channel (48-bit RGB) mastered images to 10-bit (30-bit RGB, 1024 levels per channel), 12-bit (36-bit RGB, 4096 levels per channel), or 14-bit (42-bit RGB, 16384&*8236; levels per channel) before converting to 16-bit PNG? That way the color quantize is already done, we get to store a lossless backup in the smallest space possible since PNG will only store the actual bit depth in a 16-bit PNG image (or at least from my tests in Photoshop that is indeed what seems to happen), and when newer video compression schemes come out you have a lossless-but-highly-compressed source.
I used ximagic on a TIFF file from an image sequence, used kMeans quantization to 8-bit (24-bit RGB, 256 levels per channel), 10-bit (30-bit RGB, 1024 levels per channel), and 12-bit (36-bit RGB, 4096 levels per channel)
kMeans for Color Quantization: https://lmcaraig.com/color-quantization-using-k-means
Results with file size are shown below. I used LZW compression on the TIFF files and Mixed Prediction Method on the PNG files.
Per one frame
Based on size differences and current folder of Frame Sequence Images
Per average of the total folder size of all rendered frames. For 12-bit video you are talking cutting your archive of the original frames by 2/3
Is this a solid idea or am I way off base?
[SIZE=1]
P.S. Image converter does not seem to be optimized to handle large sets of images such as these. When I clicked on the folder to select all the images, dBpoweramp Image Converter starting using the hard drive for about 5 hours before I finally ended the process and split things up into smaller batches[/SIZE]
So, let's say we have all these 16-bit TIFFs for an Image / Frame Sequence, but we know that this is the final master, color grading is done, and so anything over 10, 12, or 14 bits will be a waste of space, right? So why not have an option to quantize those final 16-bit-per channel (48-bit RGB) mastered images to 10-bit (30-bit RGB, 1024 levels per channel), 12-bit (36-bit RGB, 4096 levels per channel), or 14-bit (42-bit RGB, 16384&*8236; levels per channel) before converting to 16-bit PNG? That way the color quantize is already done, we get to store a lossless backup in the smallest space possible since PNG will only store the actual bit depth in a 16-bit PNG image (or at least from my tests in Photoshop that is indeed what seems to happen), and when newer video compression schemes come out you have a lossless-but-highly-compressed source.
I used ximagic on a TIFF file from an image sequence, used kMeans quantization to 8-bit (24-bit RGB, 256 levels per channel), 10-bit (30-bit RGB, 1024 levels per channel), and 12-bit (36-bit RGB, 4096 levels per channel)
kMeans for Color Quantization: https://lmcaraig.com/color-quantization-using-k-means
Results with file size are shown below. I used LZW compression on the TIFF files and Mixed Prediction Method on the PNG files.
Per one frame
| Filetype | 8-bit result (KB) | 10-bit result (KB) | 12-bit result (KB) | 16-bit result (KB) |
| TIFF [1080p] | 2,533 | 3,807 | 4,556 | 10,613 |
| PNG [1080p] | 2,202 | 3,002 | 3,352 | 8,166 |
| TIFF [2160p] | 8,431 | 13,301 | 16,388 | 45,853 |
| PNG [2160p] | 4,519 | 7,344 | 9,014 | 27,550 |
Based on size differences and current folder of Frame Sequence Images
| Sequence Type | 8-bit archive (TB) | 10-bit archive (TB) | 12-bit archive (TB) | 16-bit archive (TB) |
| TIFF - HD | 0.34 | 0.52 | 0.62 | 1.44 |
| PNG - HD | 0.3 | 0.41 | 0.46 | 1.11 |
| TIFF - HD @ 60fps | 0.86 | 1.29 | 1.55 | 3.61 |
| PNG - HD @ 60fps | 0.75 | 1.02 | 1.14 | 2.78 |
| TIFF - 4K | 1.15 | 1.81 | 2.23 | 6.23 |
| PNG - 4K | 0.62 | 1 | 1.23 | 3.74 |
| TIFF - 4K @ 60fps | 2.86 | 4.52 | 5.57 | 15.58 |
| PNG - 4K @ 60fps | 1.53 | 2.5 | 3.06 | 9.36 |
Per average of the total folder size of all rendered frames. For 12-bit video you are talking cutting your archive of the original frames by 2/3
Is this a solid idea or am I way off base?
[SIZE=1]
P.S. Image converter does not seem to be optimized to handle large sets of images such as these. When I clicked on the folder to select all the images, dBpoweramp Image Converter starting using the hard drive for about 5 hours before I finally ended the process and split things up into smaller batches[/SIZE]