| Pngcrush documentation |
| |
| This is the copyright notice, disclaimer, and license: |
| |
| /* |
| * COPYRIGHT NOTICE, DISCLAIMER, AND LICENSE: |
| * |
| * Copyright (c) 1998, 1999, Glenn Randers-Pehrson |
| * |
| * The pngcrush program is supplied "AS IS". The Author disclaims all |
| * warranties, expressed or implied, including, without limitation, the |
| * warranties of merchantability and of fitness for any purpose. The |
| * Author assumes no liability for direct, indirect, incidental, special, |
| * exemplary, or consequential damages, which may result from the use of |
| * the pngcrush program, even if advised of the possibility of such damage. |
| * |
| * Permission is hereby granted to use, copy, modify, and distribute this |
| * source code, or portions hereof, for any purpose, without fee, subject |
| * to the following restrictions: |
| * |
| * 1. The origin of this source code must not be misrepresented. |
| * |
| * 2. Altered versions must be plainly marked as such and must not be |
| * misrepresented as being the original source. |
| * |
| * 3. This Copyright notice, disclaimer, and license may not be removed |
| * or altered from any source or altered source distribution. |
| */ |
| |
| This is the output of "pngcrush" and "pngcrush -help": |
| |
| |
| |
| | pngcrush 1.3.5, Copyright (C) 1998, 1999, 2000 Glenn Randers-Pehrson |
| | This is a free, open-source program. Permission is |
| | granted to everyone to use pngcrush without fee. |
| | This program was built with libpng version 1.1.0a, |
| | Copyright (C) 1995, Guy Eric Schalnat, Group 42 Inc., |
| | Copyright (C) 1996, 1997 Andreas Dilger, |
| | Copyright (C) 1998, 1999, 2000 Glenn Randers-Pehrson, |
| | and zlib version 1.1.3, Copyright (c) 1998, |
| | Jean-loup Gailly and Mark Adler. |
| |
| |
| usage: pngcrush [options] infile.png outfile.png |
| pngcrush -e ext [other options] files.png ... |
| pngcrush -d dir [other options] files.png ... |
| options: |
| -brute (Use brute-force, try 114 different methods [11-124]) |
| -c color_type of output file [0, 2, 4, or 6] |
| -d directory_name (where output files will go) |
| -double_gamma (used for fixing gamma in PhotoShop 5.0/5.02 files) |
| -e extension (used for creating output filename) |
| -f user_filter [0-5] |
| -force (Write a new output file even if larger than input) |
| -g gamma (float or fixed*100000, e.g., 0.45455 or 45455) |
| -itxt b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| -l zlib_compression_level [0-9] |
| -m method [0 through 200] |
| -max maximum_IDAT_size [1 through 524288] |
| -n (no save; does not do compression or write output PNG) |
| -plte_len n (truncate PLTE) |
| -q (quiet) |
| -rem chunkname (or "alla" or "allb") |
| -replace_gamma gamma_value (float) even when file has a gAMA chunk. |
| -res dpi |
| -srgb [0, 1, 2, or 3] |
| -text b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| -trns index red green blue gray |
| -v (display more detailed information) |
| -version (display the pngcrush version) |
| -w compression_window_size [32, 16, 8, 4, 2, 1, 512] |
| -h (help) |
| -p (pause) |
| |
| |
| usage: pngcrush [options] infile.png outfile.png |
| pngcrush -e ext [other options] files.png ... |
| pngcrush -d dir [other options] files.png ... |
| |
| options: |
| -brute (Use brute-force, try 114 different methods [11-124]) |
| |
| Very time-consuming and generally not worthwhile. |
| You can restrict this option to certain filter types, |
| compression levels, or strategies by following it with |
| "-f filter", "-l level", or "-z strategy". |
| |
| -c color_type of output file [0, 2, 4, or 6] |
| |
| Color type for the output file. Future versions |
| will also allow color_type 3, if there are 256 or |
| fewer colors present in the input file. Color types |
| 4 and 6 are padded with an opaque alpha channel if |
| the input file does not have alpha information. |
| Use 0 or 2 to delete an unwanted alpha channel. |
| Default is to use same color type as the input file. |
| |
| -d directory_name (where output files will go) |
| |
| If a directory name is given, then the output |
| files are placed in it, with the same filenames as |
| those of the original files. For example, |
| you would type 'pngcrush -directory CRUSHED *.png' |
| to get *.png => CRUSHED/*.png |
| |
| -double_gamma (used for fixing gamma in PhotoShop 5.0/5.02 files) |
| |
| It has been claimed that the PS5 bug is actually |
| more complex than that, in some unspecified way. |
| |
| -e extension (used for creating output filename) |
| |
| e.g., -ext .new means *.png => *.new |
| and -e _C.png means *.png => *_C.png |
| |
| -f user_filter [0-5] |
| |
| filter to use with the method specified in the |
| preceding '-m method' or '-brute_force' argument. |
| 0: none; 1-4: use specified filter; 5: adaptive. |
| |
| -force (Write a new output file even if larger than input) |
| |
| Otherwise the input file will be copied to output |
| if it is smaller than any generated file and no chunk |
| additions, removals, or changes were requested. |
| |
| -g gamma (float or fixed*100000, e.g., 0.45455 or 45455) |
| |
| Value to insert in gAMA chunk, only if the input |
| file has no gAMA chunk. To replace an existing |
| gAMA chunk, use the '-replace_gamma' option. |
| |
| -itxt b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| |
| Compressed iTXt chunk to insert (see -text). |
| |
| -l zlib_compression_level [0-9] |
| |
| zlib compression level to use with method specified |
| with the preceding '-m method' or '-brute_force' |
| argument. |
| |
| -m method [0 through 200] |
| |
| pngcrush method to try (0 means try all of 1-10). |
| Can be repeated as in '-m 1 -m 4 -m 7'. |
| This can be useful if you run out of memory when pngcrush |
| tries methods 2, 3, 5, 6, 8, 9, or 10 which use |
| filtering and are memory intensive. Methods |
| 1, 4, and 7 use no filtering; methods 11 and up use |
| specified filter, compression level, and strategy. |
| |
| -max maximum_IDAT_size [1 through 524288] |
| |
| -n (no save; does not do compression or write output PNG) |
| |
| Useful in conjunction with -v option to get info. |
| |
| -plte_len n (truncate PLTE) |
| |
| Truncates the PLTE. Be sure not to truncate it to |
| |
| less than the greatest index present in IDAT. |
| -q (quiet) |
| |
| |
| -rem chunkname (or "alla" or "allb") |
| |
| Name of an ancillary chunk or optional PLTE to be |
| removed. Be careful with this. Please don't use |
| this feature to remove transparency, gamma, copyright, |
| or other valuable information. To remove several |
| different chunks, repeat: -rem tEXt -rem pHYs. |
| Known chunks (those in the PNG 1.1 spec or extensions |
| document) can be named with all lower-case letters, |
| so "-rem bkgd" is equivalent to "-rem bKGD". |
| Exact case is required to remove unknown chunks. |
| "-rem text" also removes zTXt. If you like to do |
| surgery with a chain-saw, "-rem alla" removes |
| all known ancillary chunks except for tRNS, and |
| "-rem allb" removes all but tRNS and gAMA. |
| |
| -replace_gamma gamma_value (float) even when file has a gAMA chunk. |
| |
| -res dpi |
| |
| Write a pHYs chunk with the given resolution. |
| |
| -srgb [0, 1, 2, or 3] |
| |
| Value of 'rendering intent' for sRGB chunk. |
| |
| -text b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| |
| tEXt chunk to insert. keyword < 80 chars, |
| |
| text < 2048 chars. For now, you can only add ten |
| tEXt, iTXt, or zTXt chunks per pngcrush run. |
| |
| -trns index red green blue gray |
| |
| Insert a tRNS chunk, if no tRNS chunk found in file. |
| You must give all five parameters regardless of the |
| color type, scaled to the output bit depth. |
| |
| -v (display more detailed information) |
| |
| Repeat the option (use "-v -v") for even more. |
| |
| -version (display the pngcrush version) |
| |
| -w compression_window_size [32, 16, 8, 4, 2, 1, 512] |
| |
| Size of the sliding compression window, in kbytes |
| (or bytes, in case of 512). It's best to |
| use the default (32) unless you run out of memory. |
| The program will use a smaller window anyway when |
| the uncompressed file is smaller than 16k. |
| |
| -z zlib_strategy [0, 1, or 2] |
| |
| zlib compression strategy to use with the preceding |
| '-m method' argument. |
| |
| -zitxt b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| |
| Compressed iTXt chunk to insert (see -text). |
| |
| -ztxt b[efore_IDAT]|a[fter_IDAT] "keyword" "text" |
| |
| zTXt chunk to insert (see -text). |
| |
| -h (help) |
| |
| Display this information. |
| |
| -p (pause) |
| |
| Wait for [enter] key before continuing display. |
| e.g., type 'pngcrush -pause -help', if the help |
| screen scrolls out of sight. |
| |