From 199adc17d0e30c00373dad0228c2ff88baa64ce6 Mon Sep 17 00:00:00 2001 From: Artem Pavlenko Date: Wed, 22 Feb 2012 17:16:07 +0000 Subject: [PATCH] fix reduced image width calc --- include/mapnik/png_io.hpp | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/mapnik/png_io.hpp b/include/mapnik/png_io.hpp index e048446c2..4ea2abc78 100644 --- a/include/mapnik/png_io.hpp +++ b/include/mapnik/png_io.hpp @@ -428,7 +428,7 @@ void save_as_png8_oct(T1 & file, T2 const& image, const unsigned max_colors = 25 else if (palette.size() == 1) { // 1 color image -> write 1-bit color depth PNG - unsigned image_width = (int(0.125*width) + 7)&~7; + unsigned image_width = width > 7 ? (int(0.125*width) + 1)&~1 : 1; unsigned image_height = height; image_data_8 reduced_image(image_width,image_height); reduce_1(image,reduced_image,trees, limits, alphaTable); @@ -441,7 +441,7 @@ void save_as_png8_oct(T1 & file, T2 const& image, const unsigned max_colors = 25 else { // <=16 colors -> write 4-bit color depth PNG - unsigned image_width = (int(0.5*width) + 3)&~3; + unsigned image_width = width > 3 ? (int(0.5*width) + 3)&~3 : 4; unsigned image_height = height; image_data_8 reduced_image(image_width,image_height); reduce_4(image, reduced_image, trees, limits, TRANSPARENCY_LEVELS, alphaTable); @@ -478,7 +478,7 @@ void save_as_png8(T1 & file, T2 const& image, T3 const & tree, else if (palette.size() == 1) { // 1 color image -> write 1-bit color depth PNG - unsigned image_width = (int(0.125*width) + 7)&~7; + unsigned image_width = width > 7 ? (int(0.125*width) + 1)&~1 : 1; unsigned image_height = height; image_data_8 reduced_image(image_width, image_height); reduced_image.set(0);