Home > Archive > Compression > May 2007 > Independent JPEG Decompress By Scanlines
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
Independent JPEG Decompress By Scanlines
|
|
| genghis86@hotmail.com 2007-05-15, 6:55 pm |
| The interface to the decompressor provided by the Independent JPEG
library is to decode the image by scanlines.
Correct me if I am wrong, but doesn't JPEG store the image in 8x8
blocks? So when you decode, you should iteratively get more and more
blocks, not scanlines!
| |
| cr88192 2007-05-15, 6:55 pm |
|
<genghis86@hotmail.com> wrote in message
news:1179271340.563040.251360@q23g2000hsg.googlegroups.com...
> The interface to the decompressor provided by the Independent JPEG
> library is to decode the image by scanlines.
>
> Correct me if I am wrong, but doesn't JPEG store the image in 8x8
> blocks? So when you decode, you should iteratively get more and more
> blocks, not scanlines!
>
who knows why they did it that way?...
maybe because they figured that is what would be convinient for writing to
image files, or something like that.
in my case, my encoders/decoders typically work a whole image at a time (I
usually implicitly assume that the image is some "sane" size).
| |
| Jim Leonard 2007-05-16, 6:56 pm |
| On May 15, 6:22 pm, genghi...@hotmail.com wrote:
> The interface to the decompressor provided by the Independent JPEG
> library is to decode the image by scanlines.
>
> Correct me if I am wrong, but doesn't JPEG store the image in 8x8
> blocks? So when you decode, you should iteratively get more and more
> blocks, not scanlines!
It was my understanding that a row of blocks is decoded, then
delivered to the host application scanline by scanline.
| |
| genghis86@hotmail.com 2007-05-21, 9:56 pm |
| On May 16, 3:31 pm, Jim Leonard <MobyGa...@gmail.com> wrote:
> It was my understanding that a row of blocks is decoded, then
> delivered to the host application scanline by scanline.
Is there any other interface? For example, can I read block by block?
| |
| Jim Leonard 2007-05-22, 9:56 pm |
| On May 21, 1:50 pm, genghi...@hotmail.com wrote:
> On May 16, 3:31 pm, Jim Leonard <MobyGa...@gmail.com> wrote:
>
>
> Is there any other interface? For example, can I read block by block?
No idea; why don't you check the library's documentation?
|
|
|
|
|