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From: Eric R. <es...@th...> - 2011-06-15 22:00:49
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James Cloos <cl...@jh...>: > Based on the git repo, the last change to PNG_LIBPNG_VER_MINOR before > these changes was from 1.2.10 to 1.4.0. There is no 1.3. > > Therefore, your proposed patch in the other reply looks correct. That's good. > There are still a bunch of api deprecation warnings, and I get the notice: > > 0 sBIT red bits not valid for 8bit/sample image > > from almost every png I try. Converting such a .sng back to png gives > the related warning: > > libpng warning: Invalid sBIT depth specified > > So there may be more api changes which affect sng but do not prevent > compilation.... Yuck. Does an sng copy built with 1.4 pass the regression tests? -- <a href="http://www.catb.org/~esr/">Eric S. Raymond</a> |
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From: James C. <cl...@jh...> - 2011-06-15 20:56:06
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> ...this clearly relates to a libpng API change, and we need to figure > out when it happened to conditionalize the code properly. Indeed. That is why I left it as a simple git diff and not git format-patch output. I looked at the libpng git repo. Change "trans" to "trans_alpha" is commit 6abea7562b which is after the bump to 1.4.0beta74 and before the bump to 1.4.0beta75. The change from trans_values to trans_color occurred in commit 56f6396137, which is 'Imported from libpng-1.4.0beta35.tar', from before the switch to git. Based on the git repo, the last change to PNG_LIBPNG_VER_MINOR before these changes was from 1.2.10 to 1.4.0. There is no 1.3. Therefore, your proposed patch in the other reply looks correct. There are still a bunch of api deprecation warnings, and I get the notice: 0 sBIT red bits not valid for 8bit/sample image from almost every png I try. Converting such a .sng back to png gives the related warning: libpng warning: Invalid sBIT depth specified So there may be more api changes which affect sng but do not prevent compilation.... -JimC -- James Cloos <cl...@jh...> OpenPGP: 1024D/ED7DAEA6 |
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From: Eric R. <es...@th...> - 2011-06-15 19:29:15
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Here's my first cut at coping with the API problem. Compiles here.
diff --git a/sngd.c b/sngd.c
index 248ac97..1ab5727 100644
--- a/sngd.c
+++ b/sngd.c
@@ -12,6 +12,21 @@ NAME
#include "png.h"
#include "sng.h"
+/* cope with API issues */
+#if PNG_LIBPNG_VER_MAJOR == 1
+ #if PNG_LIBPNG_VER_MINOR <= 2
+ #define TRANS_COLOR trans_values
+ #define TRANS_ALPHA trans
+ #endif
+ #if PNG_LIBPNG_VER_MINOR == 3
+ #error Not yet ported to 1.3
+ #endif
+ #if PNG_LIBPNG_VER_MINOR >= 4
+ #define TRANS_COLOR trans_color
+ #define TRANS_ALPHA trans_alpha
+ #endif
+#endif
+
png_structp png_ptr;
png_infop info_ptr;
@@ -794,17 +809,17 @@ static void dump_tRNS(FILE *fpout)
fprintf(fpout, "tRNS {\n");
switch (info_ptr->color_type) {
case PNG_COLOR_TYPE_GRAY:
- fprintf(fpout, " gray: %u;\n", info_ptr->trans_values.gray);
+ fprintf(fpout, " gray: %u;\n", info_ptr->TRANS_COLOR.gray);
break;
case PNG_COLOR_TYPE_RGB:
fprintf(fpout, " red: %u; green: %u; blue: %u;\n",
- info_ptr->trans_values.red,
- info_ptr->trans_values.green,
- info_ptr->trans_values.blue);
+ info_ptr->TRANS_COLOR.red,
+ info_ptr->TRANS_COLOR.green,
+ info_ptr->TRANS_COLOR.blue);
break;
case PNG_COLOR_TYPE_PALETTE:
for (i = 0; i < info_ptr->num_trans; i++)
- fprintf(fpout, " %u", info_ptr->trans[i]);
+ fprintf(fpout, " %u", info_ptr->TRANS_ALPHA[i]);
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
case PNG_COLOR_TYPE_RGB_ALPHA:
--
<a href="http://www.catb.org/~esr/">Eric S. Raymond</a>
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From: Eric R. <es...@th...> - 2011-06-15 19:13:30
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James Cloos <cl...@jh...>:
> I tried to compile sng from git. I have libpng-1.4.7 installed.
>
> First, notwithstanding the recent commits, I had to pass
>
> --with-rgbtxt=/usr/share/X11/rgb.txt
>
> to get ./configure to complete.
>
> That is fixed by:
>
> diff --git a/configure.in b/configure.in
> index b78df01..5dd6c4e 100644
> --- a/configure.in
> +++ b/configure.in
> @@ -44,7 +44,7 @@ if test -n "$with_rgbtxt"
> then
> AC_DEFINE_UNQUOTED(RGBTXT, "$with_rgbtxt", [Location of X color database])
> else
> - for dir in /etc/X11/ /usr/share/X11/rgb.txt /usr/X11R6/lib/X11 /usr/lib/X11 /usr/openwin/lib
> + for dir in /etc/X11/ /usr/share/X11/ /usr/X11R6/lib/X11 /usr/lib/X11 /usr/openwin/lib
> do
> if test -f ${dir}/rgb.txt
> then
That change is clearly correct. Taken.
On the other hand...
> Second, sngd.c fails to compile with 166 deprication warnings (52 unique)
> and these errors:
>
> :; gcc -DHAVE_CONFIG_H -I. -g -MT sngd.o -MD -MP -MF .deps/sngd.Tpo -c -o sngd.o sngd.c 2>&1 |egrep -i error
> sngd.c:797:48: error: ‘png_info’ has no member named ‘trans_values’
> sngd.c:801:15: error: ‘png_info’ has no member named ‘trans_values’
> sngd.c:802:15: error: ‘png_info’ has no member named ‘trans_values’
> sngd.c:803:15: error: ‘png_info’ has no member named ‘trans_values’
> sngd.c:807:33: error: ‘png_info’ has no member named ‘trans’
>
> After reading libpng(3), I see that this patch is required:
>
> diff --git a/sngd.c b/sngd.c
> index 248ac97..888d214 100644
> --- a/sngd.c
> +++ b/sngd.c
> @@ -794,17 +794,17 @@ static void dump_tRNS(FILE *fpout)
> fprintf(fpout, "tRNS {\n");
> switch (info_ptr->color_type) {
> case PNG_COLOR_TYPE_GRAY:
> - fprintf(fpout, " gray: %u;\n", info_ptr->trans_values.gray);
> + fprintf(fpout, " gray: %u;\n", info_ptr->trans_color.gray);
> break;
> case PNG_COLOR_TYPE_RGB:
> fprintf(fpout, " red: %u; green: %u; blue: %u;\n",
> - info_ptr->trans_values.red,
> - info_ptr->trans_values.green,
> - info_ptr->trans_values.blue);
> + info_ptr->trans_color.red,
> + info_ptr->trans_color.green,
> + info_ptr->trans_color.blue);
> break;
> case PNG_COLOR_TYPE_PALETTE:
> for (i = 0; i < info_ptr->num_trans; i++)
> - fprintf(fpout, " %u", info_ptr->trans[i]);
> + fprintf(fpout, " %u", info_ptr->trans_alpha[i]);
> break;
> case PNG_COLOR_TYPE_GRAY_ALPHA:
> case PNG_COLOR_TYPE_RGB_ALPHA:
...this clearly relates to a libpng API change, and we need to figure out
when it happened to conditionalize the code properly. Here's what I see
in my png.h:
#define PNG_LIBPNG_VER_MAJOR 1
#define PNG_LIBPNG_VER_MINOR 2
#define PNG_LIBPNG_VER_RELEASE 42
What do those constants look like for you? And does the libpng Changelog
tell you when the the API break was?
What I'm thinking is that I should define TRANS_ALPHA and TRANS_COLOR
macros that are conditionally defined by version.
--
<a href="http://www.catb.org/~esr/">Eric S. Raymond</a>
|
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From: James C. <cl...@jh...> - 2011-06-14 07:06:13
|
I tried to compile sng from git. I have libpng-1.4.7 installed.
First, notwithstanding the recent commits, I had to pass
--with-rgbtxt=/usr/share/X11/rgb.txt
to get ./configure to complete.
That is fixed by:
diff --git a/configure.in b/configure.in
index b78df01..5dd6c4e 100644
--- a/configure.in
+++ b/configure.in
@@ -44,7 +44,7 @@ if test -n "$with_rgbtxt"
then
AC_DEFINE_UNQUOTED(RGBTXT, "$with_rgbtxt", [Location of X color database])
else
- for dir in /etc/X11/ /usr/share/X11/rgb.txt /usr/X11R6/lib/X11 /usr/lib/X11 /usr/openwin/lib
+ for dir in /etc/X11/ /usr/share/X11/ /usr/X11R6/lib/X11 /usr/lib/X11 /usr/openwin/lib
do
if test -f ${dir}/rgb.txt
then
Second, sngd.c fails to compile with 166 deprication warnings (52 unique)
and these errors:
:; gcc -DHAVE_CONFIG_H -I. -g -MT sngd.o -MD -MP -MF .deps/sngd.Tpo -c -o sngd.o sngd.c 2>&1 |egrep -i error
sngd.c:797:48: error: ‘png_info’ has no member named ‘trans_values’
sngd.c:801:15: error: ‘png_info’ has no member named ‘trans_values’
sngd.c:802:15: error: ‘png_info’ has no member named ‘trans_values’
sngd.c:803:15: error: ‘png_info’ has no member named ‘trans_values’
sngd.c:807:33: error: ‘png_info’ has no member named ‘trans’
After reading libpng(3), I see that this patch is required:
diff --git a/sngd.c b/sngd.c
index 248ac97..888d214 100644
--- a/sngd.c
+++ b/sngd.c
@@ -794,17 +794,17 @@ static void dump_tRNS(FILE *fpout)
fprintf(fpout, "tRNS {\n");
switch (info_ptr->color_type) {
case PNG_COLOR_TYPE_GRAY:
- fprintf(fpout, " gray: %u;\n", info_ptr->trans_values.gray);
+ fprintf(fpout, " gray: %u;\n", info_ptr->trans_color.gray);
break;
case PNG_COLOR_TYPE_RGB:
fprintf(fpout, " red: %u; green: %u; blue: %u;\n",
- info_ptr->trans_values.red,
- info_ptr->trans_values.green,
- info_ptr->trans_values.blue);
+ info_ptr->trans_color.red,
+ info_ptr->trans_color.green,
+ info_ptr->trans_color.blue);
break;
case PNG_COLOR_TYPE_PALETTE:
for (i = 0; i < info_ptr->num_trans; i++)
- fprintf(fpout, " %u", info_ptr->trans[i]);
+ fprintf(fpout, " %u", info_ptr->trans_alpha[i]);
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
case PNG_COLOR_TYPE_RGB_ALPHA:
-JimC
--
James Cloos <cl...@jh...> OpenPGP: 1024D/ED7DAEA6
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