385 png_filter_sub(unsigned stride, uint8_t *in, uint8_t *out, unsigned len)  in png_filter_sub()  argument
391 		if (i >= stride)  in png_filter_sub()
392 			a = out[i - stride];  in png_filter_sub()
399 png_filter_up(unsigned stride __unused, uint8_t *in, uint8_t *out,  in png_filter_up()
412 png_filter_average(unsigned stride, uint8_t *in, uint8_t *out,  in png_filter_average()  argument
424 		if (i >= stride)  in png_filter_average()
425 			a = out[i - stride];  in png_filter_average()
455 png_filter_paeth(unsigned stride, uint8_t *in, uint8_t *out, uint8_t *prev_line,  in png_filter_paeth()  argument
464 		if (prev_line && i >= stride) {  in png_filter_paeth()
465 			a = out[i - stride];  in png_filter_paeth()
467 			c = prev_line[i - stride];  in png_filter_paeth()
474 			if (i >= stride)  in png_filter_paeth()
475 				a = out[i - stride];  in png_filter_paeth()
493 	unsigned stride = png->bpp;  in png_unfilter()  local
501 			for (i = 0; i < png->width * stride; i += 2) {  in png_unfilter()
509 			memcpy(data+outpos, filtered+pos, png->width * stride);  in png_unfilter()
512 			png_filter_sub(stride, filtered+pos, data+outpos,  in png_unfilter()
513 			    png->width * stride);  in png_unfilter()
517 				png_filter_up(stride, filtered+pos, data+outpos,  in png_unfilter()
518 				    data + outpos - (png->width*stride),  in png_unfilter()
519 				    png->width*stride);  in png_unfilter()
521 				png_filter_up(stride, filtered+pos, data+outpos,  in png_unfilter()
522 				    0, png->width*stride);  in png_unfilter()
527 				png_filter_average(stride, filtered+pos,  in png_unfilter()
529 				    data + outpos - (png->width*stride),  in png_unfilter()
530 				    png->width*stride);  in png_unfilter()
532 				png_filter_average(stride, filtered+pos,  in png_unfilter()
533 				    data+outpos, 0, png->width*stride);  in png_unfilter()
538 				png_filter_paeth(stride, filtered+pos,  in png_unfilter()
540 				    data + outpos - (png->width*stride),  in png_unfilter()
541 				    png->width*stride);  in png_unfilter()
543 				png_filter_paeth(stride, filtered+pos,  in png_unfilter()
544 				    data+outpos, 0, png->width*stride);  in png_unfilter()
551 		outpos += png->width * stride;  in png_unfilter()
552 		pos += png->width * stride;  in png_unfilter()