From 8e4f083438e2a6234da96f63fcceadafd5a8bd03 Mon Sep 17 00:00:00 2001 From: Carl Hetherington Date: Thu, 11 Aug 2022 16:38:24 +0200 Subject: [PATCH] Fix broken writing of 16-bit images (the pixels must be written MSB-first). --- test/test.cc | 37 ++++++++++++++++++++++++++++++++++--- 1 file changed, 34 insertions(+), 3 deletions(-) diff --git a/test/test.cc b/test/test.cc index a761eb520..9261ce43b 100644 --- a/test/test.cc +++ b/test/test.cc @@ -741,9 +741,40 @@ write_image (shared_ptr image, boost::filesystem::path file) png_set_IHDR (png_ptr, info_ptr, image->size().width, image->size().height, bits_per_pixel, png_color_type, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); - png_byte ** row_pointers = reinterpret_cast(png_malloc(png_ptr, image->size().height * sizeof(png_byte *))); - for (int i = 0; i < image->size().height; ++i) { - row_pointers[i] = (png_byte *) (image->data()[0] + i * image->stride()[0]); + auto const width = image->size().width; + auto const height = image->size().height; + auto const stride = image->stride()[0]; + + vector> data_to_write(height); + for (int y = 0; y < height; ++y) { + data_to_write[y].resize(stride); + } + + switch (image->pixel_format()) { + case AV_PIX_FMT_RGB24: + for (int y = 0; y < height; ++y) { + memcpy(data_to_write[y].data(), image->data()[0] + y * stride, stride); + } + break; + case AV_PIX_FMT_XYZ12LE: + /* 16-bit pixel values must be written MSB first */ + for (int y = 0; y < height; ++y) { + data_to_write[y].resize(stride); + uint8_t* original = image->data()[0] + y * stride; + for (int x = 0; x < width * 3; ++x) { + data_to_write[y][x * 2] = original[1]; + data_to_write[y][x * 2 + 1] = original[0]; + original += 2; + } + } + break; + default: + break; + } + + png_byte ** row_pointers = reinterpret_cast(png_malloc(png_ptr, image->size().height * sizeof(png_byte *))); + for (int y = 0; y < height; ++y) { + row_pointers[y] = reinterpret_cast(data_to_write[y].data()); } png_write_info (png_ptr, info_ptr); -- 2.30.2