Sony A7R IV: Where is the Firmware Update to Upgrade Us to Lossless-Compressed RAW Files? UPDATE: not likely to happen
Lossless-compressed raw is bit-for-bit identical in data (once uncompressed) to uncompressed raw. Uncompressed raw is the stupidest most useless format around, as all it does is waste storage space and waste time writing to card, backing up, etc. And Sony’s “Compressed” raw format has image quality problems under conditions of extreme contrast.
Fujifilm gets lossless-compressed raw right, as does just about every other camera vendor.
I have hundreds of gigabytes of uncompressed Sony raw files sucking up 2X the space they need. Sure would be nice to have a tool to redo uncompressed Sony ARW raw files so as to cut the size in half (on average)
Will anything but the Sony A1 offer lossless-compressed raw file format?
Sony has promised that the Sony A1 will incorporate a lossless-compressed raw file format, something I’ve been waiting on for years with the Sony A7R/II/III/IV.
In addition to compressed and uncompressed RAW, the Alpha 1 includes efficient lossless compression with no quality degradation, Lossless Compressed RAW.
The Sony A1 is not out yet, but the Sony A7R IV sits here waiting for a firmware update to give it the lossless-compressed raw file capability.
Will Sony be delivering firmware for the Sony A7R IV to give it lossless-compressed raw file format support?
Probably will never happen
Alex Tutbalin of LibRaw writes:
Sony A1 lossless compression is a 'normal' lossless-14-bit-JPEG compression (very similar to Canon CR2 or Nikon NEF, but with different pixel ordering). Huffman coding is used.
Most likely it is performed in hardware, so no way to provide such compression in earlier cameras if no such code/blocks exists in image processor (BIONZ).
It may be not possible to use existing 8-bit (JPEG) compression hardware in 14-bit data mode.
Software compression is not possible at present frame/data rates with camera general purpose CPU (Sony A7R-IV: 120 MB/picture x 10 fps => 1.2GB/sec of data)
Modern methods implemented in Fujifilm and/or in Canon CR3 compress better. If looked at from our side (implement decoder without *any* documentation), LJPEG (Huffman) is much easier to do.
DIGLLOYD: since the very fastest SD cards do about 300 MB/sec and many are good for half that or less, any CPU that can process data at speed from 150-300MB/sec would be in line with what the storage card can accept, which is a good solution.
I’d gladly accept a compressed-raw mode having a reduced frame rate because very little of my work needs for high frame rates.
My 2019 Mac Pro can gzip a TIF file at the sluggish speed of 39 MB/sec, so even if the camera CPUs were twice as fast, that would probably be considered too slow for general use—but I’d still use it for landscape shooting because it wouldn’t matter (single shots a few seconds apart plus memory buffering would make it a non-event).
Alex’s explanation also tells us why Fujifilm lossess compression is far superior to that of Nikon NEF or Canon CR2: Huffman Coding is primitive algorithm with relatively poor compression savings.
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