From 85155bfaa190dd49477b48296e3865115bad8e2e Mon Sep 17 00:00:00 2001
From: Rodrigo Braz Monteiro <zeratul@cellosoft.com>
Date: Mon, 3 Apr 2006 13:45:47 +0000
Subject: [PATCH] PRS encoder optimization fixed

Originally committed to SVN as r293.
---
 core/subtitle_format_prs.cpp | 23 ++++++++++++-----------
 prs/png_wrap.cpp             |  2 +-
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/core/subtitle_format_prs.cpp b/core/subtitle_format_prs.cpp
index 96b20599f..473c27af4 100644
--- a/core/subtitle_format_prs.cpp
+++ b/core/subtitle_format_prs.cpp
@@ -166,7 +166,7 @@ void PRSSubtitleFormat::WriteFile(wxString filename,wxString encoding) {
 			if (!curImage.Ok()) continue;
 
 			// Optimize image
-			//OptimizeImage(curImage);
+			OptimizeImage(curImage);
 
 			// Insert the image
 			useFrameN = framen;
@@ -182,7 +182,7 @@ void PRSSubtitleFormat::WriteFile(wxString filename,wxString encoding) {
 	// Save file
 	file.Save((const char*)filename.mb_str(wxConvLocal));
 	wxString filename2 = filename + _T(".prsa");
-	//file.SaveText((const char*)filename2.mb_str(wxConvLocal));
+	file.SaveText((const char*)filename2.mb_str(wxConvLocal));
 #endif
 }
 
@@ -459,7 +459,6 @@ std::vector<int> PRSSubtitleFormat::GetFrameRanges() {
 
 /////////////////////////////////////////////
 // Optimize the image by tweaking the colors
-#define ERROR_OF_ALPHA(a) ((a) == 0 ? 255 : 512/((int)(a)))
 #define IN_ERROR_MARGIN(col1,col2,error) ((col1 > col2 ? ((int)(col1-col2)) : ((int)(col2-col1))) <= (error))
 
 void PRSSubtitleFormat::OptimizeImage(wxImage &image) {
@@ -507,10 +506,9 @@ void PRSSubtitleFormat::OptimizeImage(wxImage &image) {
 				if (status[i] != 0) continue;
 
 				// Get error
-				error = ERROR_OF_ALPHA(alpha[i]);
-				c1 = MIN(255,c1 + MIN(128,error/2));
-				c2 = MIN(255,c2 + MIN(128,error/2));
-				c3 = MIN(255,c3 + MIN(128,error/2));
+				int a = alpha[i];
+				if (a == 0) error = 255;
+				else error = 1024/a;
 
 				// Right pixel
 				if (i != len-1 && status[i+1] == 2) {
@@ -673,10 +671,13 @@ wxImage PRSSubtitleFormat::CalculateAlpha(const unsigned char* frame1, const uns
 				else if (y > maxy) maxy = y;
 
 				// Calculate colour components
-				int mod = MAX(0,128/a-1);
-				r = MAX(0,r1-mod)*255 / a;
-				g = MAX(0,g1-mod)*255 / a;
-				b = MAX(0,b1-mod)*255 / a;
+				//int mod = MAX(0,128/a-1);
+				//r = MAX(0,r1-mod)*255 / a;
+				//g = MAX(0,g1-mod)*255 / a;
+				//b = MAX(0,b1-mod)*255 / a;
+				r = r1*255/a;
+				g = g1*255/a;
+				b = b1*255/a;
 			}
 
 			// Write to destination
diff --git a/prs/png_wrap.cpp b/prs/png_wrap.cpp
index 5f5e80b79..b1a9a5244 100644
--- a/prs/png_wrap.cpp
+++ b/prs/png_wrap.cpp
@@ -83,7 +83,7 @@ void PNGWrapper::Read(PRSVideoFrame *frame) {
 	}
 
 	// Set data reading
-	png_set_read_fn(png_ptr,this,memory_read_data);
+	png_set_read_fn(png_ptr,this,(png_rw_ptr) memory_read_data);
 
 	// Read data
 	//png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_EXPAND | PNG_TRANSFORM_PACKING | PNG_TRANSFORM_STRIP_16, NULL);