Handling large jpeg2000

[pgane]

Hi,

I'm currently using IPPv6 update 2 and I'm trying to use the samples to open a large jp2 file. I'm running into memory problems with both the UIC sample and and the jpeg2000 sample. The files I'm trying to open are satellite pictures and their resolution is around 12000 * 9000. The memory usage of the sample goes through the roof and they just run out. I think it's because of the decompression buffer being allocated beforehand ends up being very large even if the file is quite small. Unfortunately the files I'm using only have one tile according to the code. Is there I can get the sample to work with streaming buffers of a fixed size ?

What I'd like to do is read a sliding portion of the file and export it to a different format ? I don't see how to do this currently using the IPP sample code.

Any help appreciated.

Cheers,
Pascal.

[Mikhail_Kulikov__Int]

Hi,

sorry, it seems we have no ready solution.
Currently in UIC, it's possible only to read or writea file entire.
RegardingJPEG 2000 decoder itself, it's also designed to allocate buffer (more than)of 9000x12000 in your case.

Note, it's hard to implement your "streaming conversion" idea in general case, even for JPEG 2000 stream.The stream can be in raster based progression as well as inresolution-based (or in other progressions).For case of resolution-based progressionyou canget first only "small" picture that isenlarging by stream progression. So if you'd like to convert it to full-size BMP you still need to allocate a full bufferand resize it...
For some particular constraints (themode of stream, non-parallel code) it's possible to implement such an idia, but it's a particular case, which need another design of decoder.We don't have it implemented.

Regards,
Mikhail

[pgane]

Hi,

Thanks for your answer. I thought it'd be possible to specify a ROI and only decode this using JPEG2000. Basically that's what I'd like to write to file.

Cheers,
Pascal.

[Vladimir_Dudnik]

Hi Pascal,

I would recommend you to submit this as a feature request to Intel Premier Support. We will consider this request at the next version planning stage.

Regards,
Vladimir

[pgane]

Hi,

I will if we have Premier access, which I don't know right now.

Cheers,
Pascal.