Mikhail Karpenko committed changes to the Elphel git project :
Fix errors in 'read_disk' command

Mikhail Karpenko committed changes to the Elphel git project :
Add 'read_all_files' and 'read_disk' commands

Andrey Filippov committed changes to the Elphel git project :
Update README.md

Andrey Filippov committed changes to the Elphel git project :
Update README.md

Andrey Filippov committed changes to the Elphel git project :
Update README.md

AndreyFilippov committed changes to the Elphel git project :
parsing python error output in cocotb simulation

AndreyFilippov committed changes to the Elphel git project :
making cocotb to complete w/o reporting an error

AndreyFilippov committed changes to the Elphel git project :
modified doxygen docs location

Andrey Filippov committed changes to the Elphel git project :
working to add cocotb simualtion

← Older revision Revision as of 17:51, 30 June 2016 (One intermediate revision not shown)Line 1: Line 1: -Note: the JP4 mode described here is referred as "JP46" in current 8.0 firwmare  -  == JP4 Format == == JP4 Format == -We have added a special JP4 mode that bypasses the Demosaic in the FPGA and provides an image with pixels in each 16x16 macroblock that are rearranged to separate Bayer colors in individual 8x8 blocks, then encoded as monochrome. [[Demosaic_on_client_side|Demosaic]] will be applied during post-processing on the host PC. This section describe different algorithms and implementations used to provide this functionality.+JP4 format is based on JPEG compression, it was originally developed at Elphel for accurate representation of the scanned book pages and later used in other applications that involve post-processing. This format is supported in both [[353|NC353 series]] and current [[10393|NC393 series]] cameras. The standard JPEG was developed to compress images so they visually are almost the same as uncompressed but are significantly smaller in size. The goal of JP4 is camera-centric, not human-centric. It tries to preserve as much as possible of the information from the camera sensor (ideally "raw") while providing reasonable compression. The most damaging part of the color JPEG compression is the de-mosaic part of it. "Lossy" part of the compression (quantization after DCT) can be eliminated with setting compression quality to 100% that effectively disables quantization. Dynamic range compression ("gamma conversion") is usually designed to be lower than the sensor shot noise - significant for most modern small-pixel (and so low full-well capacity) sensors. That leaves the demosaic ("guessing" the missing colors in Bayer mosaic sensor outputs) a single most damaging operation. In the camera this is usually done by processing data in 3x3 or 5x5 pixel blocks and it is difficult to distinguish between variations (especially sharp) in intensity and the color tone. There are much more advanced algorithms that can be used during post-processing that will provide much better results, but they require "raw" sensor data. Or - the data saved in JP4 format.  +   +Here is a [http://community.elphel.com/jp4/jp4demo.php JP4 Demo] that illustrates this algorithm and how it is related to standard JPEG.  +   +JP4 mode bypasses the demosaic/color converiosn in the FPGA and provides an image with pixels in each 16x16 macroblock that are rearranged to separate Bayer colors in individual 8x8 blocks, then encoded as monochrome. [[Demosaic_on_client_side|Demosaic]] will be applied during post-processing on the host PC. This section describe different algorithms and implementations used to provide this functionality. Main goals: Main goals: - - compression speed improvement+* compression speed improvement - - possibility to obtain more high quality image (near to RAW)+* possibility to obtain more high quality image (near to RAW) - - drasticaly lowering data size+* drasticaly lowering data size == Different JP4 Modes in 8.X Software == == Different JP4 Modes in 8.X Software == only modes 0-2 can be processed with standard libjpeg:                  only modes 0-2 can be processed with standard libjpeg:                  Andrey.filippov

AndreyFilippov committed changes to the Elphel git project :
Added configuration for the Doxverilog 1.8.2

AndreyFilippov committed changes to the Elphel git project :
modified autogenerated .gitignore

AndreyFilippov committed changes to the Elphel git project :
added files to be generated by patching VEditor

AndreyFilippov committed changes to the Elphel git project :
updated patch for veditor

AndreyFilippov committed changes to the Elphel git project :
fixing working with multiple HDL projects open simultaneously

AndreyFilippov committed changes to the Elphel git project :
fixed after autogenerated

AndreyFilippov committed changes to the Elphel git project :
added files to be generated by patching VEditor

AndreyFilippov committed changes to the Elphel git project :
synchronized to full repo

AndreyFilippov committed changes to the Elphel git project :
added define of TRACE macro

Andrey Filippov committed changes to the Elphel git project :
more tweaking for cocotb