/* Write a VIPS image to PNG. */ static int write_vips( Write *write, int compress, int interlace, const char *profile, VipsForeignPngFilter filter, gboolean strip ) { VipsImage *in = write->in; int bit_depth; int color_type; int interlace_type; int i, nb_passes; g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || in->BandFmt == VIPS_FORMAT_USHORT ); g_assert( in->Coding == VIPS_CODING_NONE ); g_assert( in->Bands > 0 && in->Bands < 5 ); /* Catch PNG errors. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); /* Check input image. If we are writing interlaced, we need to make 7 * passes over the image. We advertise ourselves as seq, so to ensure * we only suck once from upstream, switch to WIO. */ if( interlace ) { if( !(write->memory = vips_image_copy_memory( in )) ) return( -1 ); in = write->memory; } else { if( vips_image_pio_input( in ) ) return( -1 ); } if( compress < 0 || compress > 9 ) { vips_error( "vips2png", "%s", _( "compress should be in [0,9]" ) ); return( -1 ); } /* Set compression parameters. */ png_set_compression_level( write->pPng, compress ); /* Set row filter. */ png_set_filter( write->pPng, 0, filter ); bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16; switch( in->Bands ) { case 1: color_type = PNG_COLOR_TYPE_GRAY; break; case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break; case 3: color_type = PNG_COLOR_TYPE_RGB; break; case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break; default: vips_error( "vips2png", _( "can't save %d band image as png" ), in->Bands ); return( -1 ); } interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE; png_set_IHDR( write->pPng, write->pInfo, in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT ); /* Set resolution. libpng uses pixels per meter. */ png_set_pHYs( write->pPng, write->pInfo, VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), PNG_RESOLUTION_METER ); /* Set ICC Profile. */ if( profile && !strip ) { if( strcmp( profile, "none" ) != 0 ) { void *data; size_t length; if( !(data = vips__file_read_name( profile, VIPS_ICC_DIR, &length )) ) return( -1 ); #ifdef DEBUG printf( "write_vips: " "attaching %zd bytes of ICC profile\n", length ); #endif /*DEBUG*/ png_set_iCCP( write->pPng, write->pInfo, "icc", PNG_COMPRESSION_TYPE_BASE, data, length ); } } else if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) && !strip ) { void *data; size_t length; if( vips_image_get_blob( in, VIPS_META_ICC_NAME, &data, &length ) ) return( -1 ); #ifdef DEBUG printf( "write_vips: attaching %zd bytes of ICC profile\n", length ); #endif /*DEBUG*/ png_set_iCCP( write->pPng, write->pInfo, "icc", PNG_COMPRESSION_TYPE_BASE, data, length ); } png_write_info( write->pPng, write->pInfo ); /* If we're an intel byte order CPU and this is a 16bit image, we need * to swap bytes. */ if( bit_depth > 8 && !vips_amiMSBfirst() ) png_set_swap( write->pPng ); if( interlace ) nb_passes = png_set_interlace_handling( write->pPng ); else nb_passes = 1; /* Write data. */ for( i = 0; i < nb_passes; i++ ) if( vips_sink_disc( in, write_png_block, write ) ) return( -1 ); /* The setjmp() was held by our background writer: reset it. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); png_write_end( write->pPng, write->pInfo ); return( 0 ); }
INTMASK * im_vips2imask( IMAGE *in, const char *filename ) { int width, height; INTMASK *out; double *data; int x, y; double double_result; int int_result; /* double* only: cast if necessary. */ if( in->BandFmt != IM_BANDFMT_DOUBLE ) { IMAGE *t; if( !(t = im_open( "im_vips2imask", "p" )) ) return( NULL ); if( im_clip2fmt( in, t, IM_BANDFMT_DOUBLE ) || !(out = im_vips2imask( t, filename )) ) { im_close( t ); return( NULL ); } im_close( t ); return( out ); } /* Check the image. */ if( im_incheck( in ) || im_check_uncoded( "im_vips2imask", in ) ) return( NULL ); if( in->Bands == 1 ) { width = in->Xsize; height = in->Ysize; } else if( in->Xsize == 1 ) { width = in->Bands; height = in->Ysize; } else if( in->Ysize == 1 ) { width = in->Xsize; height = in->Bands; } else { im_error( "im_vips2imask", "%s", _( "one band, nx1, or 1xn images only" ) ); return( NULL ); } data = (double *) in->data; if( !(out = im_create_imask( filename, width, height )) ) return( NULL ); /* We want to make an intmask which has the same input to output ratio * as the double image. * * Imagine convolving with the double image, what's the ratio of * brightness between input and output? We want the same ratio for the * int version, if we can. * * Imaging an input image where every pixel is 1, what will the output * be? */ double_result = 0; for( y = 0; y < height; y++ ) for( x = 0; x < width; x++ ) double_result += data[x + width * y]; double_result /= vips_image_get_scale( in ); for( y = 0; y < height; y++ ) for( x = 0; x < width; x++ ) if( in->Bands > 1 && in->Ysize == 1 ) /* Need to transpose: the image is RGBRGBRGB, * we need RRRGGGBBB. */ out->coeff[x + y * width] = VIPS_RINT( data[x * height + y] ); else out->coeff[x + y * width] = VIPS_RINT( data[x + y * width] ); out->scale = VIPS_RINT( vips_image_get_scale( in ) ); if( out->scale == 0 ) out->scale = 1; out->offset = VIPS_RINT( vips_image_get_offset( in ) ); /* Now convolve a 1 everywhere image with the int version we've made, * what do we get? */ int_result = 0; for( y = 0; y < height; y++ ) for( x = 0; x < width; x++ ) int_result += out->coeff[x + width * y]; int_result /= out->scale; /* And adjust the scale to get as close to a match as we can. */ out->scale = VIPS_RINT( out->scale + (int_result - double_result) ); if( out->scale == 0 ) out->scale = 1; return( out ); }
/* Write a VIPS image to PNG. */ static int write_vips( Write *write, int compress, int interlace ) { VipsImage *in = write->in; int bit_depth; int color_type; int interlace_type; int i, nb_passes; g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || in->BandFmt == VIPS_FORMAT_USHORT ); g_assert( in->Coding == VIPS_CODING_NONE ); g_assert( in->Bands > 0 && in->Bands < 5 ); /* Catch PNG errors. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); /* Check input image. */ if( vips_image_pio_input( in ) ) return( -1 ); if( compress < 0 || compress > 9 ) { vips_error( "vips2png", "%s", _( "compress should be in [0,9]" ) ); return( -1 ); } /* Set compression parameters. */ png_set_compression_level( write->pPng, compress ); bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16; switch( in->Bands ) { case 1: color_type = PNG_COLOR_TYPE_GRAY; break; case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break; case 3: color_type = PNG_COLOR_TYPE_RGB; break; case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break; default: g_assert( 0 ); /* Keep -Wall happy. */ return( 0 ); } interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE; png_set_IHDR( write->pPng, write->pInfo, in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT ); /* Set resolution. libpnbg uses pixels per meter. */ png_set_pHYs( write->pPng, write->pInfo, VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), PNG_RESOLUTION_METER ); /* Set ICC Profile. */ if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) ) { void *profile; size_t profile_length; if( vips_image_get_blob( in, VIPS_META_ICC_NAME, &profile, &profile_length ) ) return( -1 ); #ifdef DEBUG printf( "write_vips: attaching %zd bytes of ICC profile\n", profile_length ); #endif /*DEBUG*/ png_set_iCCP( write->pPng, write->pInfo, "icc", PNG_COMPRESSION_TYPE_BASE, profile, profile_length ); } png_write_info( write->pPng, write->pInfo ); /* If we're an intel byte order CPU and this is a 16bit image, we need * to swap bytes. */ if( bit_depth > 8 && !vips_amiMSBfirst() ) png_set_swap( write->pPng ); if( interlace ) nb_passes = png_set_interlace_handling( write->pPng ); else nb_passes = 1; /* Write data. */ for( i = 0; i < nb_passes; i++ ) if( vips_sink_disc( write->in, write_png_block, write ) ) return( -1 ); /* The setjmp() was held by our background writer: reset it. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); png_write_end( write->pPng, write->pInfo ); return( 0 ); }
/* Make a fixed-point version of a matrix. Each * out[i] = rint(in[i] * adj_scale), where adj_scale is selected so that * sum(out) = sum(in) * scale. * * Because of the vagaries of rint(), we can't just calc this, we have to * iterate and converge on the best value for adj_scale. */ void vips_vector_to_fixed_point( double *in, int *out, int n, int scale ) { double fsum; int i; int target; int sum; double high; double low; double guess; fsum = 0.0; for( i = 0; i < n; i++ ) fsum += in[i]; target = VIPS_RINT( fsum * scale ); /* As we rint() each scale element, we can get up to 0.5 error. * Therefore, by the end of the mask, we can be off by up to n/2. Our * high and low guesses are therefore n/2 either side of the obvious * answer. */ high = scale + (n + 1) / 2; low = scale - (n + 1) / 2; do { guess = (high + low) / 2.0; for( i = 0; i < n; i++ ) out[i] = VIPS_RINT( in[i] * guess ); sum = 0; for( i = 0; i < n; i++ ) sum += out[i]; if( sum == target ) break; if( sum < target ) low = guess; if( sum > target ) high = guess; /* This will typically produce about 5 iterations. */ } while( high - low > 0.01 ); if( sum != target ) { /* Spread the error out thinly over the whole array. For * example, consider the matrix: * * 3 3 9 0 * 1 1 1 * 1 1 1 * 1 1 1 * * being converted with scale = 64 (convi does this). We want * to generate a mix of 7s and 8s. */ int each_error = (target - sum) / n; int extra_error = (target - sum) % n; /* To share the residual error, we add or subtract 1 from the * first abs(extra_error) elements. */ int direction = extra_error > 0 ? 1 : -1; int n_elements = VIPS_ABS( extra_error ); for( i = 0; i < n; i++ ) out[i] += each_error; for( i = 0; i < n_elements; i++ ) out[i] += direction; } }
/* Write a VIPS image to PNG. */ static int write_vips( Write *write, int compress, int interlace, const char *profile, VipsForeignPngFilter filter, gboolean strip, gboolean palette, int colours, int Q, double dither ) { VipsImage *in = write->in; int bit_depth; int color_type; int interlace_type; int i, nb_passes; g_assert( in->BandFmt == VIPS_FORMAT_UCHAR || in->BandFmt == VIPS_FORMAT_USHORT ); g_assert( in->Coding == VIPS_CODING_NONE ); g_assert( in->Bands > 0 && in->Bands < 5 ); /* Catch PNG errors. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); /* Check input image. If we are writing interlaced, we need to make 7 * passes over the image. We advertise ourselves as seq, so to ensure * we only suck once from upstream, switch to WIO. */ if( interlace ) { if( !(write->memory = vips_image_copy_memory( in )) ) return( -1 ); in = write->memory; } else { if( vips_image_pio_input( in ) ) return( -1 ); } if( compress < 0 || compress > 9 ) { vips_error( "vips2png", "%s", _( "compress should be in [0,9]" ) ); return( -1 ); } /* Set compression parameters. */ png_set_compression_level( write->pPng, compress ); /* Set row filter. */ png_set_filter( write->pPng, 0, filter ); bit_depth = in->BandFmt == VIPS_FORMAT_UCHAR ? 8 : 16; switch( in->Bands ) { case 1: color_type = PNG_COLOR_TYPE_GRAY; break; case 2: color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break; case 3: color_type = PNG_COLOR_TYPE_RGB; break; case 4: color_type = PNG_COLOR_TYPE_RGB_ALPHA; break; default: vips_error( "vips2png", _( "can't save %d band image as png" ), in->Bands ); return( -1 ); } #ifdef HAVE_IMAGEQUANT /* Enable image quantisation to paletted 8bpp PNG if colours is set. */ if( palette ) { g_assert( colours >= 2 && colours <= 256 ); bit_depth = 8; color_type = PNG_COLOR_TYPE_PALETTE; } #else if( palette ) g_warning( "%s", _( "ignoring palette (no quantisation support)" ) ); #endif /*HAVE_IMAGEQUANT*/ interlace_type = interlace ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE; png_set_IHDR( write->pPng, write->pInfo, in->Xsize, in->Ysize, bit_depth, color_type, interlace_type, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT ); /* Set resolution. libpng uses pixels per meter. */ png_set_pHYs( write->pPng, write->pInfo, VIPS_RINT( in->Xres * 1000 ), VIPS_RINT( in->Yres * 1000 ), PNG_RESOLUTION_METER ); /* Set ICC Profile. */ if( profile && !strip ) { if( strcmp( profile, "none" ) != 0 ) { void *data; size_t length; if( !(data = vips__file_read_name( profile, vips__icc_dir(), &length )) ) return( -1 ); #ifdef DEBUG printf( "write_vips: " "attaching %zd bytes of ICC profile\n", length ); #endif /*DEBUG*/ png_set_iCCP( write->pPng, write->pInfo, "icc", PNG_COMPRESSION_TYPE_BASE, data, length ); } } else if( vips_image_get_typeof( in, VIPS_META_ICC_NAME ) && !strip ) { void *data; size_t length; if( vips_image_get_blob( in, VIPS_META_ICC_NAME, &data, &length ) ) return( -1 ); #ifdef DEBUG printf( "write_vips: attaching %zd bytes of ICC profile\n", length ); #endif /*DEBUG*/ png_set_iCCP( write->pPng, write->pInfo, "icc", PNG_COMPRESSION_TYPE_BASE, data, length ); } if( vips_image_get_typeof( in, VIPS_META_XMP_NAME ) ) { const char *str; if( vips_image_get_string( in, VIPS_META_XMP_NAME, &str ) ) return( -1 ); vips__png_set_text( write->pPng, write->pInfo, "XML:com.adobe.xmp", str ); } /* Set any "png-comment-xx-yyy" metadata items. */ if( vips_image_map( in, write_png_comment, write ) ) return( -1 ); #ifdef HAVE_IMAGEQUANT if( palette ) { VipsImage *im_index; VipsImage *im_palette; int palette_count; png_color *png_palette; png_byte *png_trans; int trans_count; if( vips__quantise_image( in, &im_index, &im_palette, colours, Q, dither ) ) return( -1 ); palette_count = im_palette->Xsize; g_assert( palette_count <= PNG_MAX_PALETTE_LENGTH ); png_palette = (png_color *) png_malloc( write->pPng, palette_count * sizeof( png_color ) ); png_trans = (png_byte *) png_malloc( write->pPng, palette_count * sizeof( png_byte ) ); trans_count = 0; for( i = 0; i < palette_count; i++ ) { VipsPel *p = (VipsPel *) VIPS_IMAGE_ADDR( im_palette, i, 0 ); png_color *col = &png_palette[i]; col->red = p[0]; col->green = p[1]; col->blue = p[2]; png_trans[i] = p[3]; if( p[3] != 255 ) trans_count = i + 1; #ifdef DEBUG printf( "write_vips: palette[%d] %d %d %d %d\n", i + 1, p[0], p[1], p[2], p[3] ); #endif /*DEBUG*/ } #ifdef DEBUG printf( "write_vips: attaching %d color palette\n", palette_count ); #endif /*DEBUG*/ png_set_PLTE( write->pPng, write->pInfo, png_palette, palette_count ); if( trans_count ) { #ifdef DEBUG printf( "write_vips: attaching %d alpha values\n", trans_count ); #endif /*DEBUG*/ png_set_tRNS( write->pPng, write->pInfo, png_trans, trans_count, NULL ); } png_free( write->pPng, (void *) png_palette ); png_free( write->pPng, (void *) png_trans ); VIPS_UNREF( im_palette ); VIPS_UNREF( write->memory ); write->memory = im_index; in = write->memory; } #endif /*HAVE_IMAGEQUANT*/ png_write_info( write->pPng, write->pInfo ); /* If we're an intel byte order CPU and this is a 16bit image, we need * to swap bytes. */ if( bit_depth > 8 && !vips_amiMSBfirst() ) png_set_swap( write->pPng ); if( interlace ) nb_passes = png_set_interlace_handling( write->pPng ); else nb_passes = 1; /* Write data. */ for( i = 0; i < nb_passes; i++ ) if( vips_sink_disc( in, write_png_block, write ) ) return( -1 ); /* The setjmp() was held by our background writer: reset it. */ if( setjmp( png_jmpbuf( write->pPng ) ) ) return( -1 ); png_write_end( write->pPng, write->pInfo ); return( 0 ); }