// Initialize png_ptr structure, and allocate any memory needed public static png_struct png_create_write_struct() { try { png_struct png_ptr = new png_struct(); try { // initialize zbuf-compression buffer png_ptr.zbuf_size = PNG.ZBUF_SIZE; png_ptr.zbuf = new byte[png_ptr.zbuf_size]; png_ptr.png_set_filter_heuristics(PNG_FILTER_HEURISTIC.DEFAULT, 1, null, null); } catch (Exception) { png_ptr.zbuf = null; png_ptr = null; return(null); } return(png_ptr); } catch (Exception) { return(null); } }
// Create a PNG structure for reading, and allocate any memory needed. public static png_struct png_create_read_struct() { try { png_struct png_ptr = new png_struct(); try { // initialize zbuf - compression buffer png_ptr.zbuf_size = PNG.ZBUF_SIZE; png_ptr.zbuf = new byte[png_ptr.zbuf_size]; switch (zlib.inflateInit(png_ptr.zstream)) { case zlib.Z_OK: break; case zlib.Z_MEM_ERROR: case zlib.Z_STREAM_ERROR: throw new PNG_Exception("zlib memory error"); default: throw new PNG_Exception("Unknown zlib error"); } png_ptr.zstream.out_buf = png_ptr.zbuf; png_ptr.zstream.next_out = 0; png_ptr.zstream.avail_out = png_ptr.zbuf_size; } catch (Exception) { png_ptr.zbuf = null; png_ptr = null; } return(png_ptr); } catch (Exception) { return(null); } }
// Create a PNG structure for reading, and allocate any memory needed. public static png_struct png_create_read_struct() { try { png_struct png_ptr=new png_struct(); try { // initialize zbuf - compression buffer png_ptr.zbuf_size=PNG.ZBUF_SIZE; png_ptr.zbuf=new byte[png_ptr.zbuf_size]; switch(zlib.inflateInit(png_ptr.zstream)) { case zlib.Z_OK: break; case zlib.Z_MEM_ERROR: case zlib.Z_STREAM_ERROR: throw new PNG_Exception("zlib memory error"); default: throw new PNG_Exception("Unknown zlib error"); } png_ptr.zstream.out_buf=png_ptr.zbuf; png_ptr.zstream.next_out=0; png_ptr.zstream.avail_out=png_ptr.zbuf_size; } catch(Exception) { png_ptr.zbuf=null; png_ptr=null; } return png_ptr; } catch(Exception) { return null; } }
// Initialize png_ptr structure, and allocate any memory needed public static png_struct png_create_write_struct() { try { png_struct png_ptr=new png_struct(); try { // initialize zbuf-compression buffer png_ptr.zbuf_size=PNG.ZBUF_SIZE; png_ptr.zbuf=new byte[png_ptr.zbuf_size]; png_ptr.png_set_filter_heuristics(PNG_FILTER_HEURISTIC.DEFAULT, 1, null, null); } catch(Exception) { png_ptr.zbuf=null; png_ptr=null; return null; } return png_ptr; } catch(Exception) { return null; } }