Author: jmb Date: Thu Sep 17 11:16:39 2009 New Revision: 9591 URL: http://source.netsurf-browser.org?rev=9591&view=rev Log: Change image data reallocation strategy. Seriously improves performance with huge image data. Modified: trunk/libnspng/src/pngread.c Modified: trunk/libnspng/src/pngread.c URL: http://source.netsurf-browser.org/trunk/libnspng/src/pngread.c?rev=9591&a... ============================================================================== --- trunk/libnspng/src/pngread.c (original) +++ trunk/libnspng/src/pngread.c Thu Sep 17 11:16:39 2009 @@ -541,24 +541,25 @@ } } - if (max_idx + 1 > bps) { + if (max_idx + 1 > bps) { + const uint32_t required_size = image->data_len + bps; uint8_t *temp; uint32_t written; /* Create/extend image buffer */ -#define OUTPUT_CHUNK_SIZE (16*1024) - while (image->data_len + bps > image->data_alloc) { - temp = ctx->alloc(image->data, - image->data_alloc + OUTPUT_CHUNK_SIZE, - ctx->pw); + if (required_size > image->data_alloc) { + /* Allocate an extra 12.5% to avoid heap thrashing */ + const uint32_t new_size = required_size + + (required_size / 8); + + temp = ctx->alloc(image->data, new_size, ctx->pw); if (temp == NULL) { return NSPNG_NOMEM; } image->data = temp; - image->data_alloc += OUTPUT_CHUNK_SIZE; - } -#undef OUTPUT_CHUNK_SIZE + image->data_alloc = new_size; + } /* Compress scanline into buffer */ written = lzf_compress(src_scanline,