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This is a nice article, but too technical, or at least technical without explanations for the casual reader. Any experts feel like updating this? Wyatt Riot 22:41, 8 September 2006 (UTC)
i think so too, even though i have a high IQ (about 146) i mean, i thought that they were data/video files that would affect the game "icy tower", because certain characters affect the way the "stuff" looks VFD642 1 january 2007
The last statement should not be in this article since it refers to another meaning of PCX. Perhaps move it to another article; creating a disambiguation page for PCX would probably be necessary then.
“ | PCX is the latest automation controller used in the Alstom Control systems . It is a variant of Industrial PC . | ” |
Hello, I improved the introduction with a general paragraph about image file formats, which can aid (I think) to understood the basis of the PCX article. If you are satisfied with the simple description, you should untag the article. Ricardo Cancho Niemietz 17:51, 28 February 2007 (UTC)
“ | The images are stored in computers as binary files, which have the necessary data to represent such images (as their size in pixels, the number of colors employed, etc), arranged internally in some way. Over the years, manufacturers developed many of such file formats, usually known by acronyms. The many software uses a given format, more de facto standard it becomes. A factor of a given format's success is its capability of data compression, due to the images usually need important amounts of RAM memory and disk space. | ” |
I comparison with BMP would be very helpful. – Wulf ( talk) 21:41, 28 January 2008 (UTC)
The Table A. Typical PCX Image Formats lists 4 plane 1 bit but not the much more common 1 plane 4 bit. Both are 16 color formats, but frankly 4 plane 1 bit PCX files are relatively rare. Naaman Brown ( talk) 17:37, 24 September 2009 (UTC)
The PCX algorithm works best in compressing B&W monochrome images such as scanned text or line drawings because they tend to have long runs of black or white. The PCX algorithm may also be efficient with 16 color images, which tend to be cartoonish with long runs of the same color. With 256 color images with few runs of the same color (such as color reduced photographs) the PCX algorithm is not efficient. Naaman Brown ( talk) 17:50, 24 September 2009 (UTC)
The statement "the only way to find the actual length of the image data is to read and process it" is not necessarily true. In my program IMAGUTIL after analyzing header data and identifying a file as a PCX image, the concluding PCX check is:
if (bits_pixel == 8) { // PCX 256 color palette is appended to end of file fseek(f_in, 0L, SEEK_END); palette_off = ftell(f_in) - sizeof(PCXcolor256) - 1; fseek(f_in, palette_off, SEEK_SET); c = fgetc(f_in); if (c != 12) // error palette_off = 0L; // signal no palette else // else retain defined palette fread(PCXcolor256, sizeof(PCXcolor256), 1, f_in); } // PCXcolor256 is worka for color conversions
(f_in points to a random access disk file. PCXcolor256 is defined as 768 bytes.) Before processing the image file you:
fseek(f_in, 0L, SEEK_SET); // reset pointer to start of file
but you do not have to read and process the image data to get the length of the file or the palette location. adding a sig Naaman Brown ( talk) 14:56, 18 November 2009 (UTC)
The description of PCX's compression confuses bytes with pixels and color values. All PCX files uses the same compression method, which works on bytes. A byte may contain several pixels or only part of a pixel. The way this is written is only valid for 8-bit indexed PCX files. 83.216.149.7 ( talk) 12:09, 10 August 2011 (UTC)
Please do not change the run length for TGA to 127. TGA uses 7 bits to indicate a run length, it does not allow zero length runs so the value zero indicates a run length of one and the value 127 indicates a run length of 128.-- 83.216.149.7 ( talk) 18:46, 15 August 2011 (UTC)
A section for Viewers has been added to this article. It says PCX is supported by many programs but only mentions IrfanView by name. As such it appears to be advertising IrfanView in some sense. Given the lack of information I don't see the purpose for a viewers section in this article, there isn't a corresponding section in other image file articles on Wikipedia so I have removed this section. 87.115.120.124 ( talk) 12:43, 26 November 2012 (UTC)
Is there a particular reason that the "green" row has only 8 Gs whereas the other rows have 9 Rs, Bs or As? 82.12.109.64 ( talk) 20:26, 18 May 2017 (UTC)
![]() | This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
|
This is a nice article, but too technical, or at least technical without explanations for the casual reader. Any experts feel like updating this? Wyatt Riot 22:41, 8 September 2006 (UTC)
i think so too, even though i have a high IQ (about 146) i mean, i thought that they were data/video files that would affect the game "icy tower", because certain characters affect the way the "stuff" looks VFD642 1 january 2007
The last statement should not be in this article since it refers to another meaning of PCX. Perhaps move it to another article; creating a disambiguation page for PCX would probably be necessary then.
“ | PCX is the latest automation controller used in the Alstom Control systems . It is a variant of Industrial PC . | ” |
Hello, I improved the introduction with a general paragraph about image file formats, which can aid (I think) to understood the basis of the PCX article. If you are satisfied with the simple description, you should untag the article. Ricardo Cancho Niemietz 17:51, 28 February 2007 (UTC)
“ | The images are stored in computers as binary files, which have the necessary data to represent such images (as their size in pixels, the number of colors employed, etc), arranged internally in some way. Over the years, manufacturers developed many of such file formats, usually known by acronyms. The many software uses a given format, more de facto standard it becomes. A factor of a given format's success is its capability of data compression, due to the images usually need important amounts of RAM memory and disk space. | ” |
I comparison with BMP would be very helpful. – Wulf ( talk) 21:41, 28 January 2008 (UTC)
The Table A. Typical PCX Image Formats lists 4 plane 1 bit but not the much more common 1 plane 4 bit. Both are 16 color formats, but frankly 4 plane 1 bit PCX files are relatively rare. Naaman Brown ( talk) 17:37, 24 September 2009 (UTC)
The PCX algorithm works best in compressing B&W monochrome images such as scanned text or line drawings because they tend to have long runs of black or white. The PCX algorithm may also be efficient with 16 color images, which tend to be cartoonish with long runs of the same color. With 256 color images with few runs of the same color (such as color reduced photographs) the PCX algorithm is not efficient. Naaman Brown ( talk) 17:50, 24 September 2009 (UTC)
The statement "the only way to find the actual length of the image data is to read and process it" is not necessarily true. In my program IMAGUTIL after analyzing header data and identifying a file as a PCX image, the concluding PCX check is:
if (bits_pixel == 8) { // PCX 256 color palette is appended to end of file fseek(f_in, 0L, SEEK_END); palette_off = ftell(f_in) - sizeof(PCXcolor256) - 1; fseek(f_in, palette_off, SEEK_SET); c = fgetc(f_in); if (c != 12) // error palette_off = 0L; // signal no palette else // else retain defined palette fread(PCXcolor256, sizeof(PCXcolor256), 1, f_in); } // PCXcolor256 is worka for color conversions
(f_in points to a random access disk file. PCXcolor256 is defined as 768 bytes.) Before processing the image file you:
fseek(f_in, 0L, SEEK_SET); // reset pointer to start of file
but you do not have to read and process the image data to get the length of the file or the palette location. adding a sig Naaman Brown ( talk) 14:56, 18 November 2009 (UTC)
The description of PCX's compression confuses bytes with pixels and color values. All PCX files uses the same compression method, which works on bytes. A byte may contain several pixels or only part of a pixel. The way this is written is only valid for 8-bit indexed PCX files. 83.216.149.7 ( talk) 12:09, 10 August 2011 (UTC)
Please do not change the run length for TGA to 127. TGA uses 7 bits to indicate a run length, it does not allow zero length runs so the value zero indicates a run length of one and the value 127 indicates a run length of 128.-- 83.216.149.7 ( talk) 18:46, 15 August 2011 (UTC)
A section for Viewers has been added to this article. It says PCX is supported by many programs but only mentions IrfanView by name. As such it appears to be advertising IrfanView in some sense. Given the lack of information I don't see the purpose for a viewers section in this article, there isn't a corresponding section in other image file articles on Wikipedia so I have removed this section. 87.115.120.124 ( talk) 12:43, 26 November 2012 (UTC)
Is there a particular reason that the "green" row has only 8 Gs whereas the other rows have 9 Rs, Bs or As? 82.12.109.64 ( talk) 20:26, 18 May 2017 (UTC)