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Convert to J2C from DPX
Posted: 2017-02-22T16:54:19-07:00
by churchwa
I am trying to batch convert DPX>J2C and am having a few issues.
The main one being that IM keeps making the J2C file using the JP2 codec. i.e. it produces a file called test.j2c but when you try and open it the software says this is a JP2 file and not a J2C.
How can a force IM to convert to a J2C file?
Re: Convert to J2C from DPX
Posted: 2017-02-22T19:33:26-07:00
by fmw42
Assuming you are using a more current version of IM and openjpeg 2.1 or higher in your IM compile, then try prefacing your output with J2C:output.j2c
Also see
http://www.imagemagick.org/script/jp2.php
Re: Convert to J2C from DPX
Posted: 2017-02-23T09:25:10-07:00
by churchwa
Thanks for the advice although I still get the same result using J2C:file.j2c
As a noob, can I ask. Having installed the latest version of IM can I assume the latest openjpeg is installed as well? (Using windows)
CMD gives me the following message after converting the file (regardless if I use the prefix or not):
convert: Deprecated fields cp_cinema or cp_rsiz are used
Please consider using only the rsiz field
See openjpeg.h documentation for more details
`OpenJP2' @ warning/jp2.c/JP2WarningHandler/236.
Re: Convert to J2C from DPX
Posted: 2017-02-23T10:20:54-07:00
by fmw42
Sorry I do not know about that.
What do you get from
Does it include JP2?
What version of openjpeg do you have on your system? You can find that from
Perhaps it is a limitation of Imagick. Does it work fine using the command line in a terminal or PHP exec() command?
Re: Convert to J2C from DPX
Posted: 2017-02-23T10:56:40-07:00
by fmw42
Re: Convert to J2C from DPX
Posted: 2017-02-23T10:58:38-07:00
by fmw42
Is there really a difference? Do you know of openjpeg supports j2c?
Re: Convert to J2C from DPX
Posted: 2017-02-23T13:23:59-07:00
by churchwa
So convert -version gives:
Version: ImageMagick 7.0.5-0 Q16 x64 2017-02-20
http://www.imagemagick.org
And J2C is in the list of formats with the module being JP2. Seems I have version 2.1.2 of openjpeg.
I have tried both convert and magick as convert is now deprecated, and get the same output.
Re: Convert to J2C from DPX
Posted: 2017-02-23T13:26:22-07:00
by churchwa
fmw42 wrote: ↑2017-02-23T10:20:54-07:00
Perhaps it is a limitation of Imagick. Does it work fine using the command line in a terminal or PHP exec() command?
I am running it all from command line.
We are feeding in approx 50meg 4K files and the subsequent j2c files are only 1.2meg.
Does this sound right, seems very small.
I have done -quality 0 for lossless and the resolution comes out at 4k which is also correct.
Re: Convert to J2C from DPX
Posted: 2017-02-23T15:19:58-07:00
by fmw42
Sorry, I do not know the difference between JP2 and J2C. I could not find on Google any document that explained the difference other than suffix.