Wednesday, December 24, 2014

Bing Crosby’s “White Christmas”

I recently got the European version of Bing Crosby’s White Christmas CD from a local store here in Sweden, cat. no. MCD 18226. I discovered that this version is different from the US one; the European version seems to be based on a 1963 LP release of Merry Christmas, which is in “simulated stereo” and which has added reverb, while the US version is based on the 1955 release, which is in mono with no reverb.

Monday, May 5, 2014

Escape Sequences in RIFF Files

I find it very interesting that although Microsoft states in their Multimedia Programming Interface and Data Specifications 1.0 that escape sequences like \r, \n, \370, etc. can be used in string chunks in a RIFF (Resource Interchange File Format) file like WAV and AVI, most programs, including Microsoft’s own Windows Media Player, will let these escape sequences pass through unprocessed.

Thursday, April 24, 2014

InfoList

InfoList is a simple Perl script that lets you edit the INFO list chunk in a RIFF (Resource Interchange File Format) file, such as WAVE, RMID and AVI.

Saturday, April 12, 2014

icctext

Based on my need for a tool to edit text tags in an ICC profile, I have written a simple command line utility called icctext that lets you do just that. I hope that it might prove useful to others as well.

Tuesday, March 25, 2014

ImgView Updates

ImgView now uses a file open dialog with the help of YAD. More readable variable names in the configuration file and the environment.

Wednesday, March 12, 2014

ImgView and CMYK ICC Profile Support in TIFF

I have modified libtiff some more to make TIFFReadRGBAImage() return CMYK data as CMYK instead of RGBA. As a consequence, ImgView now supports CMYK ICC profiles in TIFF as well.

Tuesday, March 11, 2014

Updates to ImgView Color Management

ImgView now supports RGB, Gray and CMYK profiles in JPEG, and RGB and Gray ICC profiles in TIFF and PNG. Furthermore, it is now possible to define default RGB, Gray and CMYK profiles for images without an embedded ICC profile.

Saturday, March 8, 2014

ICC Profile Support in ImgView

ImgView for Unix now sup­ports RGB and CMYK ICC pro­files in JPEG, and RGB ICC pro­files in TIFF and PNG. Please note that the color management code is still rather immature.

Monday, February 24, 2014

Back to TIFF

I have converted all my PNG format pictures (back) to TIFF. I have been using this format in the past, before I put the pictures online. Since the TIFF support in web browsers is close to non‐existent, I decided to use PNG until I found a better solution. Nowadays computers are much faster than they were in the past, and it is finally feasible to convert TIFF to PNG on the fly for web display, albeit with some delay when processing very large images.

Thanks goes to Bob Friesenhahn for his valuable input regarding TIFF technicalities, and his role as the driving force behind the excellent GraphicsMagick software package, which I find much more stable and bug‐free than ImageMagick, which should perhaps be renamed as “ImageTragick”? Just kidding.

Sunday, February 16, 2014

Test Images

I have collected various test images over the years, some of them which are hard to find nowadays. Please pay a visit if you happen to be interested.

Sunday, January 26, 2014

Chroma Sub‐Sampling in JPEG Exif Files

On page 14 in the Exif 2.3 specification, under 4.4.3, “Pixel Composition and Sampling”, the following is stated:

“When compressed data is used, the combination shall be Y:Cb:Cr = 4:2:2 or Y:Cb:Cr = 4:2:0.”

Why the heck isn’t a combination of 4:4:4 (i.e. no sub‐sampling) allowed? This will produce the highest quality JPEG compressed images, and many times there is a noticeable difference between using 4:4:4 and using 4:2:2 or 4:2:0. Incomprehensible.

Thursday, January 9, 2014

pcdtoppm

pcdtoppm is a mod­i­fi­ca­tion of the pcdtojpeg Pho­to CD con­ver­sion util­i­ty that out­puts PPM rather than JPEG.