heic to jpg conversion

[Brian Inglis]

On 2020-08-13 04:13, Fergus Daly via Cygwin wrote:
>>> Does Cygwin include the capability to convert heic to jpg (or png or anything else Windows-readable)?
>>> I tried "convert" (previously all-powerful) but that does not work (in any obvious way, anyway).
>>> Thank you!
> 
>> Works for me. What does `type convert` say?
> 
> I have this:
> 
> ~/tmp> type convert
> convert is /usr/bin/convert
> ~/tmp> ls -x
> L1a.heic  L2a.heic 
> ~/tmp> file *
> L1a.heic: ISO Media
> L2a.heic: ISO Media
> ~/tmp> convert L1a.heic L1a.jpg
> convert: no decode delegate for this image format `HEIC' @ error/constitute.c/ReadImage/560.
> convert: no images defined `L1a.jpg' @ error/convert.c/ConvertImageCommand/3258.
> 
> (BTW, in the above dialogue, should ISO Media read IOS Media?)

Apparently not although it came from MPEG developments of Apple Quicktime format
which gave rise to a slew of ISO standards:

	https://en.wikipedia.org/wiki/High_Efficiency_Image_File_Format

is part of ISO/IEC 23008-12 MPEG-H Standard, which also includes HEVC High
Efficiency Video Coding ITU-T H.265/.1/.2, some ITU-T H series supplements, and
MMT MPEG Media Transport;
it appears to be a specialization of ISO/IEC 14496-12:2004-2015 MPEG-4 Part 12
base media file format aka ISO/IEC 15444-12:2004-2015 JPEG 2000 Part 12 which
was dropped in 2017 in favour of the former, which is available in

http://standards.iso.org/ittf/PubliclyAvailableStandards/c068960_ISO_IEC_14496-12_2015.zip.


So HEIF would be a better file format label, whereas ISO media includes the
above (which not many people would think of), but could also imply ISO 9660:1988
for optical disks and archive images thereof (which most people would think of),
possibly including any or all of IEEE Rock Ridge (POSIX compatible extensions),
MS Joliet "Unicode" name extensions, El Torito bootable CD extensions, and/or
Apple ISO 9660 MacOS file extensions;
that also applies to the later replacement OSTA Optical Storage Technology
Association ISO/IEC 13346:1995-1999/ECMA-167:1997 UDF Universal Disk Format.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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