[libpng16] Updated the documentation about CRC and ADLER32 handling.

This commit is contained in:
Glenn Randers-Pehrson 2016-09-26 10:32:24 -05:00
parent 394be58371
commit 04dab1e82d
4 changed files with 14 additions and 4 deletions

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@ -42,6 +42,7 @@ Version 1.6.26beta01 [September 26, 2016]
Merged pngtest.c with libpng-1.7.0beta84/pngtest.c Merged pngtest.c with libpng-1.7.0beta84/pngtest.c
Version 1.6.26beta02 [September 26, 2016] Version 1.6.26beta02 [September 26, 2016]
Updated the documentation about CRC and ADLER32 handling.
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@ -5720,6 +5720,7 @@ Version 1.6.26beta01 [September 26, 2016]
Merged pngtest.c with libpng-1.7.0beta84/pngtest.c Merged pngtest.c with libpng-1.7.0beta84/pngtest.c
Version 1.6.26beta02 [September 26, 2016] Version 1.6.26beta02 [September 26, 2016]
Updated the documentation about CRC and ADLER32 handling.
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@ -467,8 +467,9 @@ the default, use
The values for png_set_crc_action() say how libpng is to handle CRC errors in The values for png_set_crc_action() say how libpng is to handle CRC errors in
ancillary and critical chunks, and whether to use the data contained ancillary and critical chunks, and whether to use the data contained
therein. Note that it is impossible to "discard" data in a critical therein. Starting with libpng-1.6.26, this also governs how an ADLER32 error
chunk. is handled while reading the IDAT chunk. Note that it is impossible to
"discard" data in a critical chunk.
Choices for (int) crit_action are Choices for (int) crit_action are
PNG_CRC_DEFAULT 0 error/quit PNG_CRC_DEFAULT 0 error/quit
@ -485,6 +486,9 @@ Choices for (int) ancil_action are
PNG_CRC_QUIET_USE 4 quiet/use data PNG_CRC_QUIET_USE 4 quiet/use data
PNG_CRC_NO_CHANGE 5 use the current value PNG_CRC_NO_CHANGE 5 use the current value
When the setting for crit_action is PNG_CRC_QUIET_USE, the CRC and ADLER32
checksums are not only ignored, but they are not evaluated.
Setting up callback code Setting up callback code
You can set up a callback function to handle any unknown chunks in the You can set up a callback function to handle any unknown chunks in the

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@ -977,8 +977,9 @@ the default, use
The values for png_set_crc_action() say how libpng is to handle CRC errors in The values for png_set_crc_action() say how libpng is to handle CRC errors in
ancillary and critical chunks, and whether to use the data contained ancillary and critical chunks, and whether to use the data contained
therein. Note that it is impossible to "discard" data in a critical therein. Starting with libpng-1.6.26, this also governs how an ADLER32 error
chunk. is handled while reading the IDAT chunk. Note that it is impossible to
"discard" data in a critical chunk.
Choices for (int) crit_action are Choices for (int) crit_action are
PNG_CRC_DEFAULT 0 error/quit PNG_CRC_DEFAULT 0 error/quit
@ -995,6 +996,9 @@ Choices for (int) ancil_action are
PNG_CRC_QUIET_USE 4 quiet/use data PNG_CRC_QUIET_USE 4 quiet/use data
PNG_CRC_NO_CHANGE 5 use the current value PNG_CRC_NO_CHANGE 5 use the current value
When the setting for crit_action is PNG_CRC_QUIET_USE, the CRC and ADLER32
checksums are not only ignored, but they are not evaluated.
.SS Setting up callback code .SS Setting up callback code
You can set up a callback function to handle any unknown chunks in the You can set up a callback function to handle any unknown chunks in the