frankg wrote:
I think you're onto something re the header as I said above - I installed and ran Irfanview (to try and Save As a psd) but it cant open the files and there is no preview available (the preview box is checked) . I get an error message saying it cant read the file header. However I think it's a long shot to copy/paste "the first 500 or so bytes". How would you do it anyway?
There is a fixed size header of only 26 bytes only which encodes the following information in BigEndian integers:
signature (4B) = '8BPS'
version (2B) (typically = 1)
reserved [6]
channels (2B)
rows (4B)
cols (4B)
depth (2B)
mode (2B)
In the unlikely event that: 1) those 26 bytes are damaged, and 2) you can restore them all to their correct values, and 3) the remainder of the file is undamaged, then you might have a chance. Otherwise, more sophisticated salvaging would be needed. Maybe the tools other people have cited go the extra mile.
The remainder is a complex structure whose layout and contents differs for every file (see source code cited in other post for specifics). In addition, as mentioned, some elements are not publicly documented.
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