pam: sync with new changes

support for pitch (writer) - not by GPUJPEG used (yet?)

Author: MartinPulec

src/utils/image_delegate.c

@@ -235,7 +235,8 @@ int pampnm_save_delegate(const char *filename, const struct gpujpeg_image_parame
         return -1;
     }
 
-    bool ret = pam_write(filename, param_image->width, param_image->height, depth, 255, (const unsigned char *) data, pnm);
+    const bool ret = pam_write(filename, param_image->width, param_image->width, param_image->height, depth, 255,
+                               (const unsigned char*)data, pnm);
     return ret ? 0 : -1;
 }
 

src/utils/pam.c

@@ -37,6 +37,7 @@
 
 #include <ctype.h>
 #include <errno.h>
+#include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -227,7 +228,10 @@ bool pam_read(const char *filename, struct pam_metadata *info, unsigned char **d
         return true;
 }
 
-bool pam_write(const char *filename, unsigned int width, unsigned int height, int ch_count, int maxval, const unsigned char *data, bool pnm) {
+bool pam_write(const char *filename, unsigned int width, unsigned int pitch,
+               unsigned int height, int ch_count, int maxval,
+               const unsigned char *data, bool pnm)
+{
         errno = 0;
 #ifdef _WIN32
         FILE *file = _wfopen(mbs_to_wstr(filename), L"wb");
@@ -267,9 +271,19 @@ bool pam_write(const char *filename, unsigned int width, unsigned int height, in
                         "ENDHDR\n",
                         width, height, ch_count, maxval, tuple_type);
         }
-        size_t len = (size_t) width * height * ch_count * (maxval <= 255 ? 1 : 2);
+        const size_t linesize = (size_t)  height * ch_count * (maxval <= 255 ? 1 : 2);
+        const size_t len = width * linesize;
         errno = 0;
-        size_t bytes_written = fwrite((const char *) data, 1, len, file);
+        size_t bytes_written = 0;
+        if (pitch == PAM_PITCH_CONTINUOUS || width == pitch) {
+                bytes_written = fwrite((const char *) data, 1, len, file);
+        } else {
+                for (unsigned y = 0; y < height; ++y) {
+                        bytes_written += fwrite((const char *)data +
+                                                    ((size_t)y * pitch),
+                                                1, linesize, file);
+                }
+        }
         if (bytes_written != len) {
                 fprintf(stderr, "Unable to write PAM/PNM data - length %zd, written %zd: %s\n",
                         len, bytes_written, strerror(errno));

src/utils/pam.h

@@ -49,18 +49,53 @@
 extern "C" {
 #endif
 
+/// metadata read from file
 struct pam_metadata {
-        int width;
-        int height;
-        int ch_count;
-        int maxval;
-        bool bitmap_pbm; // bitmap data is stored in PBM format (1 bit per pixel, line aligned to whole byte, 1 is black /"ink on"/),
-                         // otherwise 1 byte per pixel, 1 is white "light on"); if .depth != 1 || .maxval != 1, this value is undefined
+        int width;    ///< image width
+        int height;   ///< image height
+        int ch_count; ///< number of channels
+        int maxval;   ///< sample maximal value (typically but not necessarily
+                      ///< 255)
+        bool bitmap_pbm; ///< bitmap data is stored in PBM format (1 bit per
+                         ///< pixel, line aligned to whole byte, 1 is black
+                         ///< /"ink on"/), otherwise 1 byte per pixel, 1 is
+                         ///< white "light on"); if .depth != 1 || .maxval != 1,
+                         ///< this value is undefined
 };
 
+/**
+ * read PAM/PNM file
+ *
+ * @param      filename   file name
+ * @param[out] info       pointer to metadata struct
+ * @param[out] data       pointer to byte array, can be 0, in which case no data
+ *                        are written (only metadata read )
+ * @param[out] allocaltor allocator to alloc @ref data; if 0, no data are
+ *                        read/allocated, only @ref info set
+ */
 bool pam_read(const char *filename, struct pam_metadata *info, unsigned char **data, void *(*allocator)(size_t));
-bool pam_write(const char *filename, unsigned int width, unsigned int height,
-               int ch_count, int maxval, const unsigned char *data, bool pnm);
+
+enum {
+        PAM_PITCH_CONTINUOUS = 0,
+};
+
+/**
+ * write PAM or PNM file
+ *
+ * @param filename file name to be written to
+ * @param width    image width
+ * @param pitch    input line pitch in bytes; PAM_PITCH_CONTINUOUS can be used
+ *                 if input pitch == width * ch_count * (maxval <= 255 ? 1 : 2)
+ * @param height   image height
+ * @param ch_count image channel count (1-4 for output PAM, 1 or 3 for PNM, see
+ *                 @ref pnm)
+ * @param maxval   maximal sample value, typically 255 for 8-bit
+ * @param data     bytes to be written
+ * @param pnm      use PNM file (instead of PAM)
+ */
+bool pam_write(const char *filename, unsigned int width, unsigned int pitch,
+               unsigned int height, int ch_count, int maxval,
+               const unsigned char *data, bool pnm);
 
 #ifdef __cplusplus
 } // extern "C"