Dear Dr. Taubman: I just start a project about region of interesting. There are some questions. 1)In which .c file, the weight ROI's distortion is calculated....
Hi David, Thank you very much. I have found the function parse_packet_header(). There is another question I want to ask about. Where can I get the contribution...
Dear Dr Taubman: I compress the image to JP2 with only a layer. I want to know: 1) where that each block is truncted according to given rate. 2) How to record...
When compressing with -frag using kdu_compress there is a bug that causes it to fail when the compressed image is larger than 2Gigbytes. The bug is in...
HI Steve, Thanks for catching and reporting this. I am just about to send out v4.5 but can include the fix easily. The bug might not have been caught because...
Hi, all, I have some question about the usage of Cweight and hope can get the answers here: According to the usage of kdu_compress, we can supply a separate...
Greetings. I am running into a build error for PowerPC/Linux with Altivec. Here is the output that I am getting: powerpc-7450-linux-gnu-g++ -I../common -O2...
Dear Dr Taubman, In the decoder, I'd like to build the ROI mask which is used during the encoding process. I have kakadu V2.2.3: 1. in the encoder, all...
Hi i've been testing the code provided in the JPEG2000 Image Compression Fundamentals, standards and practice. It is quite fast! However i'm especially...
Greetings. I would like to recommend removal of the argument 'bool allow_exchange' from the virtual 'push' and 'pull' functions. This argument is never used in...
Hi Angus, There is a bug here. I was not able to create a file which would not display using v4.5, so it is possible that the problem is partly rectified...
Greetings, I am not an expert in image processing, but I have a question... JPEG2000 supports ROI using some methods including maxshift. However, it also...
Hi Theodore, You cannot generally distinguish between foreground and background based around magnitudes alone, because any coefficient which gets decoded as 0...
Hi Manuel, JPIP is very interesting for GIS applications and Kakadu is up to the task. However, I am not sure what you mean by "Is kakadu prepared to the ...
Hi Steve, You are right that the argument is not currently used. The purpose of the argument is to allow for internal implementations in which line buffers...
BlankHi Ji, With regard to your first question, did you miss the usage statement for "Cweight"? You can use something like Cweight:C0=1 Cweight:C1=0.2...
... While tracking down invalid promotions of bool to int, I just noticed that those arguments were not being used. I figured there had to be some good reason...
Greetings. After some slash and burn patching and a few other hacks, I have Linux-PowerPC Altivec working for Kakadu. The interesting thing is that I actually...
Hi all, We all know codeblocks are compressed and decompressed independently and errors constrained in one codeblock won't affect others. But can anyone tell...
HI Alec, The key misunderstanding here is that random access is not at the pixel level. It operates only at the level of code-blocks, which is pretty course....
Hi Carrot Lea, You can get total distortion (quite accurately) by summing up the cumulative distortion reductions associated with all coding passes after the...
Hi all, I am using the free kdu_show program to view a MJ2 file I made. Each frame is PAL resolution (720x576) and compressed 20:1. When I use kdu_show I only...
... That sounds about right. You will not get much better with Morgan's codec from my experience. If you want full frame rate, you'll have to do it in...
Hi David, Thanks for your reply. In "subsection 10.6.2" of the book by Taubman and Marcellin, the decompressor can implicitly recover the foreground membership...
HI Darren, "kdu_show" does not use DirectX or DirectShow; although it certainly could. To get an idea how much extra effort is being taken up in the actual...
HI Steve, This I really cannot explain. Perhaps your processor is trying to emulate the Altivec instructions. The Altivec code was originally contributed by...
Hi Theodore, I think you are confused as to what "quantization index" means. K_max is not the quantization index; it is the maximum number of bit-planes which...
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