Questions on Jpeg image processing on Arduino Due

Hi There,

I am very new to Arduino world and I would like to get some helps from you guys about the jpeg image processing. XD

All I need is to take a 640x480 8bit grey photo in jpeg ( output from the camera ) and convert it into an array (i.e 0 = white and 255 = black and each number represent a pixel of the photo ) and send it out one row after another one.

I know that the Arduino Due has 96KB of SRAM and I am guessing this is enough to do the work ?

Also, is there any resources (code / ideas , etc...) about converting jpeg into array with arduino ?

I did some search on the previous post about image processing and it seems to me that the biggest issue was the hardware limit ( not enough ram) , but I believe it has been solved now ( 640 pixel x 8bit/pixel x 1byte/8bit =~ 0.6KB each row)

Thank you so much , any comment helps :)

Place to start is with file format , here is the link

http://www.fileformat.info/format/jpeg/egff.htm

How are you going to get the image? I am looking at Due for same reason - more memory. I tried to add external SRAM on Uno, but it just would not work reliably at any SPI speed. Cheers Vaclav

and send it out one row after another one

There's the tricky bit. JPEG works on 8 x 8 pixel blocks, so to send a row at a time, you'd have to buffer eight whole rows. Huffman tables are going to consume a fair amount of RAM unless you can guarantee that they'll be the same from image to image.

I doubt its trivial to get (parts of?) libjpeg working on the device, but Atmel have a library for it, various folks seem to be doing it: http://compgroups.net/comp.arch.embedded/libjpeg-+-cortex-m3/1299783