[libpng16] Implement eXIf chunk support
diff --git a/ANNOUNCE b/ANNOUNCE
index 4896a96..0448062 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -59,6 +59,7 @@
overflow' check that is on by default with -Wall -Wextra.
Version 1.6.31beta05 [July 11, 2017]
+ Added eXIf chunk support.
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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diff --git a/CHANGES b/CHANGES
index 3e07b17..18e90d6 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5889,6 +5889,7 @@
overflow' check that is on by default with -Wall -Wextra.
Version 1.6.31beta05 [July 11, 2017]
+ Added eXIf chunk support.
Send comments/corrections/commendations to png-mng-implement at lists.sf.net
(subscription required; visit
diff --git a/libpng-manual.txt b/libpng-manual.txt
index 2903f92..a6251f9 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1453,6 +1453,11 @@
the single transparent color for
non-paletted images (PNG_INFO_tRNS)
+ png_get_eXIf(png_ptr, info_ptr, &exif);
+ (PNG_INFO_eXIf)
+
+ exif - Exif profile (array of png_byte)
+
png_get_hIST(png_ptr, info_ptr, &hist);
(PNG_INFO_hIST)
@@ -2498,6 +2503,7 @@
PNG_INFO_gAMA, PNG_INFO_sBIT,
PNG_INFO_cHRM, PNG_INFO_PLTE,
PNG_INFO_tRNS, PNG_INFO_bKGD,
+ PNG_INFO_eXIf,
PNG_INFO_hIST, PNG_INFO_pHYs,
PNG_INFO_oFFs, PNG_INFO_tIME,
PNG_INFO_pCAL, PNG_INFO_sRGB,
@@ -3097,6 +3103,11 @@
single transparent color for
non-paletted images (PNG_INFO_tRNS)
+ png_set_eXIf(png_ptr, info_ptr, exif);
+
+ hist - Exif profile (array of
+ png_byte) (PNG_INFO_eXIf)
+
png_set_hIST(png_ptr, info_ptr, hist);
hist - histogram of palette (array of
@@ -5205,6 +5216,11 @@
enforced, and the palette was always limited to 256 entries. An over-length
PLTE chunk found in an input PNG is silently truncated.
+Starting with libpng-1.6.31, the eXIf chunk is supported. Libpng does not
+attempt to decode the Exif profile; it simply returns a byte array
+containing the profile to the calling application which must do its own
+decoding.
+
XIII. Detecting libpng
The png_get_io_ptr() function has been present since libpng-0.88, has never
diff --git a/libpng.3 b/libpng.3
index 9dec52b..62298f8 100644
--- a/libpng.3
+++ b/libpng.3
@@ -97,6 +97,8 @@
\fBpng_byte png_get_header_version (png_const_structp \fIpng_ptr\fP\fB);\fP
+\fBpng_uint_32 png_get_eXIf (png_const_structp \fP\fIpng_ptr\fP\fB, png_const_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fI*exif\fP\fB);\fP
+
\fBpng_uint_32 png_get_hIST (png_const_structp \fP\fIpng_ptr\fP\fB, png_const_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fI*hist\fP\fB);\fP
\fBpng_uint_32 png_get_iCCP (png_const_structp \fP\fIpng_ptr\fP\fB, png_const_infop \fP\fIinfo_ptr\fP\fB, png_charpp \fP\fIname\fP\fB, int \fP\fI*compression_type\fP\fB, png_bytepp \fP\fIprofile\fP\fB, png_uint_32 \fI*proflen\fP\fB);\fP
@@ -347,6 +349,8 @@
\fBvoid png_set_gray_to_rgb (png_structp \fIpng_ptr\fP\fB);\fP
+\fBvoid png_set_eXIf (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_bytep \fIexif\fP\fB);\fP
+
\fBvoid png_set_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_16p \fIhist\fP\fB);\fP
\fBvoid png_set_iCCP (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_const_charp \fP\fIname\fP\fB, int \fP\fIcompression_type\fP\fB, png_const_bytep \fP\fIprofile\fP\fB, png_uint_32 \fIproflen\fP\fB);\fP
@@ -1963,6 +1967,11 @@
the single transparent color for
non-paletted images (PNG_INFO_tRNS)
+ png_get_eXIf(png_ptr, info_ptr, &exif);
+ (PNG_INFO_eXIf)
+
+ exif - Exif profile (array of png_byte)
+
png_get_hIST(png_ptr, info_ptr, &hist);
(PNG_INFO_hIST)
@@ -3008,6 +3017,7 @@
PNG_INFO_gAMA, PNG_INFO_sBIT,
PNG_INFO_cHRM, PNG_INFO_PLTE,
PNG_INFO_tRNS, PNG_INFO_bKGD,
+ PNG_INFO_eXIf,
PNG_INFO_hIST, PNG_INFO_pHYs,
PNG_INFO_oFFs, PNG_INFO_tIME,
PNG_INFO_pCAL, PNG_INFO_sRGB,
@@ -3607,6 +3617,11 @@
single transparent color for
non-paletted images (PNG_INFO_tRNS)
+ png_set_eXIf(png_ptr, info_ptr, exif);
+
+ hist - Exif profile (array of
+ png_byte) (PNG_INFO_eXIf)
+
png_set_hIST(png_ptr, info_ptr, hist);
hist - histogram of palette (array of
@@ -5715,6 +5730,11 @@
enforced, and the palette was always limited to 256 entries. An over-length
PLTE chunk found in an input PNG is silently truncated.
+Starting with libpng-1.6.31, the eXIf chunk is supported. Libpng does not
+attempt to decode the Exif profile; it simply returns a byte array
+containing the profile to the calling application which must do its own
+decoding.
+
.SH XIII. Detecting libpng
The png_get_io_ptr() function has been present since libpng-0.88, has never
diff --git a/png.c b/png.c
index 3a7d6f0..2081d73 100644
--- a/png.c
+++ b/png.c
@@ -615,6 +615,16 @@
}
#endif
+#ifdef PNG_eXIf_SUPPORTED
+ /* Free any eXIf entry */
+ if (((mask & PNG_FREE_EXIF) & info_ptr->free_me) != 0)
+ {
+ png_free(png_ptr, info_ptr->exif);
+ info_ptr->exif = NULL;
+ info_ptr->valid &= ~PNG_INFO_eXIf;
+ }
+#endif
+
#ifdef PNG_hIST_SUPPORTED
/* Free any hIST entry */
if (((mask & PNG_FREE_HIST) & info_ptr->free_me) != 0)
diff --git a/png.h b/png.h
index 62d6ac6..92f9bd1 100644
--- a/png.h
+++ b/png.h
@@ -776,6 +776,7 @@
#define PNG_INFO_sPLT 0x2000U /* ESR, 1.0.6 */
#define PNG_INFO_sCAL 0x4000U /* ESR, 1.0.6 */
#define PNG_INFO_IDAT 0x8000U /* ESR, 1.0.6 */
+#define PNG_INFO_eXIf 0x10000U /* GR-P, 1.6.31 */
/* This is used for the transformation routines, as some of them
* change these values for the row. It also should enable using
@@ -1788,7 +1789,8 @@
#define PNG_FREE_PLTE 0x1000U
#define PNG_FREE_TRNS 0x2000U
#define PNG_FREE_TEXT 0x4000U
-#define PNG_FREE_ALL 0x7fffU
+#define PNG_FREE_EXIF 0x8000U /* Added at libpng-1.6.31 */
+#define PNG_FREE_ALL 0xffffU
#define PNG_FREE_MUL 0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
#ifdef PNG_USER_MEM_SUPPORTED
@@ -2007,6 +2009,13 @@
png_fixed_point int_blue_Z))
#endif
+#ifdef PNG_eXIf_SUPPORTED
+PNG_EXPORT(246, png_uint_32, png_get_eXIf, (png_const_structrp png_ptr,
+ png_inforp info_ptr, png_bytep *exif));
+PNG_EXPORT(247, void, png_set_eXIf, (png_const_structrp png_ptr,
+ png_inforp info_ptr, const png_bytep exif));
+#endif
+
#ifdef PNG_gAMA_SUPPORTED
PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr,
png_const_inforp info_ptr, double *file_gamma))
@@ -2025,9 +2034,6 @@
#ifdef PNG_hIST_SUPPORTED
PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr,
png_inforp info_ptr, png_uint_16p *hist));
-#endif
-
-#ifdef PNG_hIST_SUPPORTED
PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr,
png_inforp info_ptr, png_const_uint_16p hist));
#endif
@@ -3253,7 +3259,7 @@
* one to use is one more than this.)
*/
#ifdef PNG_EXPORT_LAST_ORDINAL
- PNG_EXPORT_LAST_ORDINAL(245);
+ PNG_EXPORT_LAST_ORDINAL(247);
#endif
#ifdef __cplusplus
diff --git a/pngget.c b/pngget.c
index 141c393..ace9e63 100644
--- a/pngget.c
+++ b/pngget.c
@@ -773,6 +773,24 @@
}
#endif
+#ifdef PNG_eXIf_SUPPORTED
+png_uint_32 PNGAPI
+png_get_eXIf(png_const_structrp png_ptr, png_inforp info_ptr,
+ png_bytep *exif)
+{
+ png_debug1(1, "in %s retrieval function", "eXIf");
+
+ if (png_ptr != NULL && info_ptr != NULL &&
+ (info_ptr->valid & PNG_INFO_eXIf) != 0 && exif != NULL)
+ {
+ *exif = info_ptr->exif;
+ return (PNG_INFO_eXIf);
+ }
+
+ return (0);
+}
+#endif
+
#ifdef PNG_hIST_SUPPORTED
png_uint_32 PNGAPI
png_get_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
diff --git a/pnginfo.h b/pnginfo.h
index 361ed8b..6e6d46a 100644
--- a/pnginfo.h
+++ b/pnginfo.h
@@ -185,6 +185,11 @@
png_byte phys_unit_type; /* resolution type (see PNG_RESOLUTION_ below) */
#endif
+#ifdef PNG_eXIf_SUPPORTED
+ int num_exif;
+ png_bytep exif;
+#endif
+
#ifdef PNG_hIST_SUPPORTED
/* The hIST chunk contains the relative frequency or importance of the
* various palette entries, so that a viewer can intelligently select a
diff --git a/pngpriv.h b/pngpriv.h
index 663608b..7c273bd 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -842,6 +842,7 @@
#define png_PLTE PNG_U32( 80, 76, 84, 69)
#define png_bKGD PNG_U32( 98, 75, 71, 68)
#define png_cHRM PNG_U32( 99, 72, 82, 77)
+#define png_eXIf PNG_U32(101, 88, 73, 102) /* registered July 2017 */
#define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
#define png_gAMA PNG_U32(103, 65, 77, 65)
#define png_gIFg PNG_U32(103, 73, 70, 103)
@@ -1441,6 +1442,11 @@
png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
#endif
+#ifdef PNG_READ_eXIf_SUPPORTED
+PNG_INTERNAL_FUNCTION(void,png_handle_eXIf,(png_structrp png_ptr,
+ png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
+#endif
+
#ifdef PNG_READ_gAMA_SUPPORTED
PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
diff --git a/pngrutil.c b/pngrutil.c
index bf3ef62..9cde648 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -2009,6 +2009,44 @@
}
#endif
+#ifdef PNG_READ_eXIf_SUPPORTED
+void /* PRIVATE */
+png_handle_eXIf(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
+{
+ unsigned int i;
+ png_bytep eXIf_buf;
+
+ png_debug(1, "in png_handle_eXIf");
+
+ if ((png_ptr->mode & PNG_HAVE_IHDR) == 0)
+ png_chunk_error(png_ptr, "missing IHDR");
+
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_eXIf) != 0)
+ {
+ png_crc_finish(png_ptr, length);
+ png_chunk_benign_error(png_ptr, "duplicate");
+ return;
+ }
+
+ eXIf_buf = png_voidcast(png_bytep,
+ png_malloc_warn(png_ptr, length));
+
+ for (i = 0; i < length; i++)
+ {
+ png_byte buf[1];
+ png_crc_read(png_ptr, buf, 1);
+ eXIf_buf[i] = buf[0];
+ }
+
+ if (png_crc_finish(png_ptr, 0) != 0)
+ return;
+
+ info_ptr->num_exif = length;
+
+ png_set_eXIf(png_ptr, info_ptr, eXIf_buf);
+}
+#endif
+
#ifdef PNG_READ_hIST_SUPPORTED
void /* PRIVATE */
png_handle_hIST(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
diff --git a/pngset.c b/pngset.c
index 2bb575d..9984735 100644
--- a/pngset.c
+++ b/pngset.c
@@ -134,6 +134,39 @@
#endif /* cHRM */
+#ifdef PNG_eXIf_SUPPORTED
+void PNGAPI
+png_set_eXIf(png_const_structrp png_ptr, png_inforp info_ptr,
+ const png_bytep eXIf_buf)
+{
+ int i;
+
+ png_debug1(1, "in %s storage function", "eXIf");
+
+ if (png_ptr == NULL || info_ptr == NULL)
+ return;
+
+ png_free_data(png_ptr, info_ptr, PNG_FREE_EXIF, 0);
+
+ info_ptr->exif = png_voidcast(png_bytep, png_malloc_warn(png_ptr,
+ info_ptr->num_exif));
+
+ if (info_ptr->exif == NULL)
+ {
+ png_warning(png_ptr, "Insufficient memory for eXIf chunk data");
+
+ return;
+ }
+
+ info_ptr->free_me |= PNG_FREE_EXIF;
+
+ for (i = 0; i < info_ptr->num_exif; i++)
+ info_ptr->exif[i] = eXIf_buf[i];
+
+ info_ptr->valid |= PNG_INFO_eXIf;
+}
+#endif /* eXIf */
+
#ifdef PNG_gAMA_SUPPORTED
void PNGFAPI
png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
diff --git a/pngstruct.h b/pngstruct.h
index 749d7e3..1e1c5f8 100644
--- a/pngstruct.h
+++ b/pngstruct.h
@@ -479,5 +479,8 @@
png_colorspace colorspace;
#endif
#endif
+
+/* New member added in libpng-1.6.30 */
+ int num_exif;
};
#endif /* PNGSTRUCT_H */
diff --git a/pngtest.c b/pngtest.c
index 01e4143..77e25e1 100644
--- a/pngtest.c
+++ b/pngtest.c
@@ -1192,6 +1192,14 @@
}
}
#endif
+#ifdef PNG_eXIf_SUPPORTED
+ {
+ png_bytep exif;
+
+ if (png_get_eXIf(read_ptr, read_info_ptr, &exif) != 0)
+ png_set_eXIf(write_ptr, write_info_ptr, exif);
+ }
+#endif
#ifdef PNG_hIST_SUPPORTED
{
png_uint_16p hist;
@@ -1530,6 +1538,14 @@
}
}
#endif
+#ifdef PNG_eXIf_SUPPORTED
+ {
+ png_bytep exif;
+
+ if (png_get_eXIf(read_ptr, end_info_ptr, &exif) != 0)
+ png_set_eXIf(write_ptr, write_end_info_ptr, exif);
+ }
+#endif
#ifdef PNG_tIME_SUPPORTED
{
png_timep mod_time;
diff --git a/pngwutil.c b/pngwutil.c
index dd80058..348bb52 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -1473,6 +1473,37 @@
}
#endif
+#ifdef PNG_WRITE_eXIf_SUPPORTED
+/* Write the Exif data */
+void /* PRIVATE */
+png_write_eXIf(png_structrp png_ptr, png_bytep exif, int num_exif)
+{
+ int i;
+ png_byte buf[3];
+
+ png_debug(1, "in png_write_eXIf");
+
+ if (num_exif > (int)png_ptr->num_exif)
+ {
+ png_debug2(3, "num_exif = %d, png_ptr->num_exif = %d", num_exif,
+ png_ptr->num_exif);
+
+ png_warning(png_ptr, "Invalid number of exif bytes specified");
+ return;
+ }
+
+ png_write_chunk_header(png_ptr, png_eXIf, (png_uint_32)(num_exif));
+
+ for (i = 0; i < num_exif; i++)
+ {
+ buf[i] = exif[i];
+ png_write_chunk_data(png_ptr, buf, (png_size_t)1);
+ }
+
+ png_write_chunk_end(png_ptr);
+}
+#endif
+
#ifdef PNG_WRITE_hIST_SUPPORTED
/* Write the histogram */
void /* PRIVATE */
diff --git a/scripts/pnglibconf.dfa b/scripts/pnglibconf.dfa
index 4d4e13b..cd7aaaf 100644
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -741,6 +741,8 @@
# Ancillary chunks
chunk bKGD
chunk cHRM enables COLORSPACE
+# enable eXIf only after chunk is approved
+chunk eXIf
chunk gAMA enables GAMMA
chunk hIST
chunk iCCP enables COLORSPACE, GAMMA
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index a901395..eb7048f 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -84,6 +84,7 @@
#define PNG_READ_USER_TRANSFORM_SUPPORTED
#define PNG_READ_bKGD_SUPPORTED
#define PNG_READ_cHRM_SUPPORTED
+#define PNG_READ_eXIf_SUPPORTED
#define PNG_READ_gAMA_SUPPORTED
#define PNG_READ_hIST_SUPPORTED
#define PNG_READ_iCCP_SUPPORTED
@@ -153,6 +154,7 @@
#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
#define PNG_WRITE_bKGD_SUPPORTED
#define PNG_WRITE_cHRM_SUPPORTED
+#define PNG_WRITE_eXIf_SUPPORTED
#define PNG_WRITE_gAMA_SUPPORTED
#define PNG_WRITE_hIST_SUPPORTED
#define PNG_WRITE_iCCP_SUPPORTED
@@ -170,6 +172,7 @@
#define PNG_WRITE_zTXt_SUPPORTED
#define PNG_bKGD_SUPPORTED
#define PNG_cHRM_SUPPORTED
+#define PNG_eXIf_SUPPORTED
#define PNG_gAMA_SUPPORTED
#define PNG_hIST_SUPPORTED
#define PNG_iCCP_SUPPORTED
diff --git a/scripts/symbols.def b/scripts/symbols.def
index 89782c9..0636509 100644
--- a/scripts/symbols.def
+++ b/scripts/symbols.def
@@ -250,3 +250,5 @@
png_get_palette_max @243
png_set_option @244
png_image_write_to_memory @245
+ png_get_eXIf @246
+ png_set_eXIf @247
