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Merge branch 'master' of git://github.com/deftomat/libvips into deftomat-master

This commit is contained in:
John Cupitt 2019-07-06 11:01:02 +01:00
parent 0706d65484 1b54684650
commit 00676a2166
7 changed files with 305 additions and 241 deletions
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1
ChangeLog
View File

@ -1,5 +1,6 @@
20/6/19 started 8.9.0
- add vips_image_get/set_array_int()
- disable webp alpha output if all frame fill the canvas and are solid
24/5/19 started 8.8.1
- improve realpath() use on older libc

13
cplusplus/include/vips/VImage8.h
View File

@ -351,6 +351,12 @@ public:
vips_image_set_int( this->get_image(), field, value );
}
void
set( const char *field, int *value, int n )
{
vips_image_set_array_int( this->get_image(), field, value, n );
}
void
set( const char *field, double value )
{
@ -388,6 +394,13 @@ public:
return( value );
}
void
get_array_int( const char *field, int **out, int *n ) const
{
if( vips_image_get_array_int( this->get_image(), field, out, n ) )
throw( VError() );
}
double
get_double( const char *field ) const
{

380
libvips/foreign/gifload.c
View File

@ -27,7 +27,7 @@
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
@ -90,10 +90,10 @@
/* Added in giflib5.
*/
#ifndef HAVE_GIFLIB_5
#define DISPOSAL_UNSPECIFIED 0
#define DISPOSE_DO_NOT 1
#define DISPOSE_BACKGROUND 2
#define DISPOSE_PREVIOUS 3
#define DISPOSAL_UNSPECIFIED 0
#define DISPOSE_DO_NOT 1
#define DISPOSE_BACKGROUND 2
#define DISPOSE_PREVIOUS 3
#endif
#define VIPS_TYPE_FOREIGN_LOAD_GIF (vips_foreign_load_gif_get_type())
@ -132,7 +132,7 @@ typedef struct _VipsForeignLoadGif {
gboolean has_transparency;
gboolean has_colour;
/* Delays between frames (in miliseconds).
/* Delays between frames (in milliseconds).
*/
int *delays;
@ -142,7 +142,7 @@ typedef struct _VipsForeignLoadGif {
/* The GIF comment, if any.
*/
char *comment;
char *comment;
/* The number of pages (frame) in the image.
*/
@ -199,12 +199,12 @@ typedef struct _VipsForeignLoadGifClass {
int (*open)( VipsForeignLoadGif *gif );
} VipsForeignLoadGifClass;
G_DEFINE_ABSTRACT_TYPE( VipsForeignLoadGif, vips_foreign_load_gif,
G_DEFINE_ABSTRACT_TYPE( VipsForeignLoadGif, vips_foreign_load_gif,
VIPS_TYPE_FOREIGN_LOAD );
/* From gif2rgb.c ... offsets and jumps for interlaced GIF images.
*/
static int
static int
InterlacedOffset[] = { 0, 4, 2, 1 },
InterlacedJumps[] = { 8, 8, 4, 2 };
@ -214,50 +214,50 @@ static const char *
vips_foreign_load_gif_errstr( int error_code )
{
#ifdef HAVE_GIFLIB_5
return( GifErrorString( error_code ) );
return( GifErrorString( error_code ) );
#else /*!HAVE_GIFLIB_5*/
switch( error_code ) {
case D_GIF_ERR_OPEN_FAILED:
return( _( "Failed to open given file" ) );
return( _( "Failed to open given file" ) );
case D_GIF_ERR_READ_FAILED:
return( _( "Failed to read from given file" ) );
return( _( "Failed to read from given file" ) );
case D_GIF_ERR_NOT_GIF_FILE:
return( _( "Data is not a GIF file" ) );
return( _( "Data is not a GIF file" ) );
case D_GIF_ERR_NO_SCRN_DSCR:
return( _( "No screen descriptor detected" ) );
return( _( "No screen descriptor detected" ) );
case D_GIF_ERR_NO_IMAG_DSCR:
return( _( "No image descriptor detected" ) );
return( _( "No image descriptor detected" ) );
case D_GIF_ERR_NO_COLOR_MAP:
return( _( "Neither global nor local color map" ) );
return( _( "Neither global nor local color map" ) );
case D_GIF_ERR_WRONG_RECORD:
return( _( "Wrong record type detected" ) );
return( _( "Wrong record type detected" ) );
case D_GIF_ERR_DATA_TOO_BIG:
return( _( "Number of pixels bigger than width * height" ) );
return( _( "Number of pixels bigger than width * height" ) );
case D_GIF_ERR_NOT_ENOUGH_MEM:
return( _( "Failed to allocate required memory" ) );
return( _( "Failed to allocate required memory" ) );
case D_GIF_ERR_CLOSE_FAILED:
return( _( "Failed to close given file" ) );
return( _( "Failed to close given file" ) );
case D_GIF_ERR_NOT_READABLE:
return( _( "Given file was not opened for read" ) );
return( _( "Given file was not opened for read" ) );
case D_GIF_ERR_IMAGE_DEFECT:
return( _( "Image is defective, decoding aborted" ) );
return( _( "Image is defective, decoding aborted" ) );
case D_GIF_ERR_EOF_TOO_SOON:
return( _( "Image EOF detected, before image complete" ) );
return( _( "Image EOF detected, before image complete" ) );
default:
return( _( "Unknown error" ) );
return( _( "Unknown error" ) );
}
#endif /*HAVE_GIFLIB_5*/
}
@ -270,7 +270,7 @@ vips_foreign_load_gif_error_vips( VipsForeignLoadGif *gif, int error )
const char *message;
if( (message = vips_foreign_load_gif_errstr( error )) )
vips_error( class->nickname, "%s", message );
vips_error( class->nickname, "%s", message );
}
static void
@ -281,14 +281,14 @@ vips_foreign_load_gif_error( VipsForeignLoadGif *gif )
error = 0;
#ifdef HAVE_GIFLIB_5
if( gif->file )
if( gif->file )
error = gif->file->Error;
#else
error = GifLastError();
#else
error = GifLastError();
#endif
if( error )
vips_foreign_load_gif_error_vips( gif, error );
if( error )
vips_foreign_load_gif_error_vips( gif, error );
}
static void
@ -296,16 +296,16 @@ vips_foreign_load_gif_close( VipsForeignLoadGif *gif )
{
#ifdef HAVE_GIFLIB_5
if( gif->file ) {
int error;
int error;
if( DGifCloseFile( gif->file, &error ) == GIF_ERROR )
if( DGifCloseFile( gif->file, &error ) == GIF_ERROR )
vips_foreign_load_gif_error_vips( gif, error );
gif->file = NULL;
}
#else
#else
if( gif->file ) {
if( DGifCloseFile( gif->file ) == GIF_ERROR )
vips_foreign_load_gif_error_vips( gif, GifLastError() );
if( DGifCloseFile( gif->file ) == GIF_ERROR )
vips_foreign_load_gif_error_vips( gif, GifLastError() );
gif->file = NULL;
}
#endif
@ -316,13 +316,13 @@ vips_foreign_load_gif_dispose( GObject *gobject )
{
VipsForeignLoadGif *gif = (VipsForeignLoadGif *) gobject;
vips_foreign_load_gif_close( gif );
vips_foreign_load_gif_close( gif );
VIPS_UNREF( gif->frame );
VIPS_UNREF( gif->previous );
VIPS_FREE( gif->comment );
VIPS_FREE( gif->line );
VIPS_FREE( gif->delays );
VIPS_UNREF( gif->frame );
VIPS_UNREF( gif->previous );
VIPS_FREE( gif->comment );
VIPS_FREE( gif->line );
VIPS_FREE( gif->delays );
G_OBJECT_CLASS( vips_foreign_load_gif_parent_class )->
dispose( gobject );
@ -346,7 +346,7 @@ vips_foreign_load_gif_is_a_buffer( const void *buf, size_t len )
const guchar *str = (const guchar *) buf;
if( len >= 4 &&
str[0] == 'G' &&
str[0] == 'G' &&
str[1] == 'I' &&
str[2] == 'F' &&
str[3] == '8' )
@ -368,31 +368,31 @@ vips_foreign_load_gif_is_a( const char *filename )
}
static int
vips_foreign_load_gif_ext_next( VipsForeignLoadGif *gif,
vips_foreign_load_gif_ext_next( VipsForeignLoadGif *gif,
GifByteType **extension )
{
if( DGifGetExtensionNext( gif->file, extension ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
if( *extension )
VIPS_DEBUG_MSG( "gifload: EXTENSION_NEXT\n" );
if( *extension )
VIPS_DEBUG_MSG( "gifload: EXTENSION_NEXT\n" );
return( 0 );
}
static int
vips_foreign_load_gif_code_next( VipsForeignLoadGif *gif,
vips_foreign_load_gif_code_next( VipsForeignLoadGif *gif,
GifByteType **extension )
{
if( DGifGetCodeNext( gif->file, extension ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
if( *extension )
VIPS_DEBUG_MSG( "gifload: CODE_NEXT\n" );
if( *extension )
VIPS_DEBUG_MSG( "gifload: CODE_NEXT\n" );
return( 0 );
}
@ -400,7 +400,7 @@ vips_foreign_load_gif_code_next( VipsForeignLoadGif *gif,
/* Quickly scan an image record.
*/
static int
vips_foreign_load_gif_scan_image_record( VipsForeignLoadGif *gif )
vips_foreign_load_gif_scan_image_record( VipsForeignLoadGif *gif )
{
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( gif );
GifFileType *file = gif->file;
@ -420,8 +420,8 @@ vips_foreign_load_gif_scan_image_record( VipsForeignLoadGif *gif )
file->Image.Height < 1 ||
file->Image.Height > 10000 ||
file->Image.Top + file->Image.Height > file->SHeight ) {
vips_error( class->nickname, "%s", _( "bad frame size" ) );
return( -1 );
vips_error( class->nickname, "%s", _( "bad frame size" ) );
return( -1 );
}
/* Test for a non-greyscale colourmap for this frame.
@ -430,7 +430,7 @@ vips_foreign_load_gif_scan_image_record( VipsForeignLoadGif *gif )
map ) {
int i;
for( i = 0; i < map->ColorCount; i++ )
for( i = 0; i < map->ColorCount; i++ )
if( map->Colors[i].Red != map->Colors[i].Green ||
map->Colors[i].Green != map->Colors[i].Blue ) {
gif->has_colour = TRUE;
@ -441,7 +441,7 @@ vips_foreign_load_gif_scan_image_record( VipsForeignLoadGif *gif )
/* Step over compressed image data.
*/
do {
if( vips_foreign_load_gif_code_next( gif, &extension ) )
if( vips_foreign_load_gif_code_next( gif, &extension ) )
return( -1 );
} while( extension != NULL );
@ -458,17 +458,17 @@ vips_foreign_load_gif_scan_application_ext( VipsForeignLoadGif *gif,
*/
have_netscape = FALSE;
if( extension[0] == 11 &&
vips_isprefix( "NETSCAPE2.0", (const char*) (extension + 1) ) )
vips_isprefix( "NETSCAPE2.0", (const char*) (extension + 1) ) )
have_netscape = TRUE;
while( extension != NULL ) {
if( vips_foreign_load_gif_ext_next( gif, &extension ) )
return( -1 );
return( -1 );
if( have_netscape &&
extension &&
extension[0] == 3 &&
extension[1] == 1 )
extension[1] == 1 )
gif->loop = extension[2] | (extension[3] << 8);
}
@ -479,21 +479,21 @@ static int
vips_foreign_load_gif_scan_comment_ext( VipsForeignLoadGif *gif,
GifByteType *extension )
{
VIPS_DEBUG_MSG( "gifload: type: comment\n" );
VIPS_DEBUG_MSG( "gifload: type: comment\n" );
if( !gif->comment ) {
if( !gif->comment ) {
/* Up to 257 with a NULL terminator.
*/
char comment[257];
vips_strncpy( comment, (char *) (extension + 1), 256 );
comment[extension[0]] = '\0';
gif->comment = g_strdup( comment );
gif->comment = g_strdup( comment );
}
while( extension != NULL )
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif, &extension ) )
return( -1 );
return( -1 );
return( 0 );
}
@ -504,52 +504,52 @@ vips_foreign_load_gif_scan_extension( VipsForeignLoadGif *gif )
GifByteType *extension;
int ext_code;
if( DGifGetExtension( gif->file, &ext_code, &extension ) ==
if( DGifGetExtension( gif->file, &ext_code, &extension ) ==
GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
if( extension )
switch( ext_code ) {
case GRAPHICS_EXT_FUNC_CODE:
if( extension )
switch( ext_code ) {
case GRAPHICS_EXT_FUNC_CODE:
if( extension[0] == 4 &&
extension[1] & 0x1 ) {
VIPS_DEBUG_MSG( "gifload: has transp.\n" );
VIPS_DEBUG_MSG( "gifload: has transp.\n" );
gif->has_transparency = TRUE;
}
if( gif->n_pages % 64 == 0 ) {
if( gif->n_pages % 64 == 0 )
gif->delays = (int *) g_realloc( gif->delays, (gif->n_pages + 64) * sizeof(int) );
}
gif->delays[gif->n_pages] = (extension[2] | (extension[3] << 8)) * 10;
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif,
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif,
&extension ) )
return( -1 );
return( -1 );
break;
case APPLICATION_EXT_FUNC_CODE:
if( vips_foreign_load_gif_scan_application_ext( gif,
case APPLICATION_EXT_FUNC_CODE:
if( vips_foreign_load_gif_scan_application_ext( gif,
extension ) )
return( -1 );
return( -1 );
break;
case COMMENT_EXT_FUNC_CODE:
if( vips_foreign_load_gif_scan_comment_ext( gif,
if( vips_foreign_load_gif_scan_comment_ext( gif,
extension ) )
return( -1 );
return( -1 );
break;
default:
/* Step over any NEXT blocks for unknown extensions.
*/
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif,
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif,
&extension ) )
return( -1 );
return( -1 );
break;
}
@ -560,41 +560,41 @@ static int
vips_foreign_load_gif_set_header( VipsForeignLoadGif *gif, VipsImage *image )
{
vips_image_init_fields( image,
gif->file->SWidth, gif->file->SHeight * gif->n,
gif->file->SWidth, gif->file->SHeight * gif->n,
(gif->has_colour ? 3 : 1) + (gif->has_transparency ? 1 : 0),
VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
gif->has_colour ?
gif->has_colour ?
VIPS_INTERPRETATION_sRGB : VIPS_INTERPRETATION_B_W,
1.0, 1.0 );
vips_image_pipelinev( image, VIPS_DEMAND_STYLE_FATSTRIP, NULL );
if( vips_object_argument_isset( VIPS_OBJECT( gif ), "n" ) )
vips_image_set_int( image,
vips_image_set_int( image,
VIPS_META_PAGE_HEIGHT, gif->file->SHeight );
vips_image_set_int( image, VIPS_META_N_PAGES, gif->n_pages );
vips_image_set_int( image, "gif-loop", gif->loop );
if( gif->delays ) {
vips_image_set_int( image, "gif-delay", VIPS_RINT( gif->delays[0] / 10.0 ) );
vips_image_set_int( image,
"gif-delay", VIPS_RINT( gif->delays[0] / 10.0 ) );
vips_image_set_array_int( image, "delay", gif->delays, gif->n_pages );
} else {
} else
vips_image_set_int( image, "gif-delay", 4 );
}
if( gif->comment )
if( gif->comment )
vips_image_set_string( image, "gif-comment", gif->comment );
return( 0 );
}
/* Attempt to quickly scan a GIF and discover what we need for our header. We
* need to scan the whole file to get n_pages, transparency and colour.
* need to scan the whole file to get n_pages, transparency and colour.
*/
static int
vips_foreign_load_gif_header( VipsForeignLoad *load )
{
VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( load );
VipsForeignLoadGifClass *gif_class =
VipsForeignLoadGifClass *gif_class =
(VipsForeignLoadGifClass *) VIPS_OBJECT_GET_CLASS( load );
VipsForeignLoadGif *gif = (VipsForeignLoadGif *) load;
@ -605,17 +605,17 @@ vips_foreign_load_gif_header( VipsForeignLoad *load )
gif->n_pages = 0;
do {
do {
if( DGifGetRecordType( gif->file, &record ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
switch( record ) {
case IMAGE_DESC_RECORD_TYPE:
if( DGifGetImageDesc( gif->file ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
/* Read in the image record.
@ -654,8 +654,8 @@ vips_foreign_load_gif_header( VipsForeignLoad *load )
if( gif->page < 0 ||
gif->n <= 0 ||
gif->page + gif->n > gif->n_pages ) {
vips_error( class->nickname, "%s", _( "bad page number" ) );
return( -1 );
vips_error( class->nickname, "%s", _( "bad page number" ) );
return( -1 );
}
/* And set the output vips header from what we've learned.
@ -705,13 +705,13 @@ vips_foreign_load_gif_render_line( VipsForeignLoadGif *gif,
iq = (guint32 *) q;
for( x = 0; x < width; x++ ) {
VipsPel v = p[x];
if( v == gif->transparency ) {
/* In DISPOSE_DO_NOT mode, the previous frame shows
* through (ie. we do nothing). In all other modes,
* through (ie. we do nothing). In all other modes,
* it's just transparent.
*/
if( gif->dispose != DISPOSE_DO_NOT )
if( gif->dispose != DISPOSE_DO_NOT )
iq[x] = 0;
}
else
@ -721,11 +721,11 @@ vips_foreign_load_gif_render_line( VipsForeignLoadGif *gif,
}
}
/* Render the current gif frame into an RGBA buffer. GIFs can accumulate,
/* Render the current gif frame into an RGBA buffer. GIFs can accumulate,
* depending on the current dispose mode.
*/
static int
vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
{
GifFileType *file = gif->file;
@ -733,11 +733,11 @@ vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
*/
vips_foreign_load_gif_build_cmap( gif );
/* BACKGROUND means we reset the frame to 0 (transparent) before we
/* BACKGROUND means we reset the frame to 0 (transparent) before we
* render the next set of pixels.
*/
if( gif->dispose == DISPOSE_BACKGROUND )
memset( VIPS_IMAGE_ADDR( gif->frame, 0, 0 ), 0,
if( gif->dispose == DISPOSE_BACKGROUND )
memset( VIPS_IMAGE_ADDR( gif->frame, 0, 0 ), 0,
VIPS_IMAGE_SIZEOF_IMAGE( gif->frame ) );
/* PREVIOUS means we init the frame with the frame before last, ie. we
@ -745,11 +745,11 @@ vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
*
* Anything other than PREVIOUS, we must update the previous buffer,
*/
if( gif->dispose == DISPOSE_PREVIOUS )
if( gif->dispose == DISPOSE_PREVIOUS )
memcpy( VIPS_IMAGE_ADDR( gif->frame, 0, 0 ),
VIPS_IMAGE_ADDR( gif->previous, 0, 0 ),
VIPS_IMAGE_SIZEOF_IMAGE( gif->frame ) );
else
else
memcpy( VIPS_IMAGE_ADDR( gif->previous, 0, 0 ),
VIPS_IMAGE_ADDR( gif->frame, 0, 0 ),
VIPS_IMAGE_SIZEOF_IMAGE( gif->frame ) );
@ -760,25 +760,25 @@ vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
VIPS_DEBUG_MSG( "vips_foreign_load_gif_render: "
"interlaced frame of %d x %d pixels at %d x %d\n",
file->Image.Width, file->Image.Height,
file->Image.Left, file->Image.Top );
file->Image.Left, file->Image.Top );
for( i = 0; i < 4; i++ ) {
int y;
for( y = InterlacedOffset[i];
for( y = InterlacedOffset[i];
y < file->Image.Height;
y += InterlacedJumps[i] ) {
VipsPel *q = VIPS_IMAGE_ADDR( gif->frame,
VipsPel *q = VIPS_IMAGE_ADDR( gif->frame,
file->Image.Left, file->Image.Top + y );
if( DGifGetLine( gif->file, gif->line,
if( DGifGetLine( gif->file, gif->line,
file->Image.Width ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
vips_foreign_load_gif_render_line( gif,
file->Image.Width, q, gif->line );
vips_foreign_load_gif_render_line( gif,
file->Image.Width, q, gif->line );
}
}
}
@ -788,20 +788,20 @@ vips_foreign_load_gif_render( VipsForeignLoadGif *gif )
VIPS_DEBUG_MSG( "vips_foreign_load_gif_render: "
"non-interlaced frame of %d x %d pixels at %d x %d\n",
file->Image.Width, file->Image.Height,
file->Image.Left, file->Image.Top );
file->Image.Left, file->Image.Top );
for( y = 0; y < file->Image.Height; y++ ) {
VipsPel *q = VIPS_IMAGE_ADDR( gif->frame,
VipsPel *q = VIPS_IMAGE_ADDR( gif->frame,
file->Image.Left, file->Image.Top + y );
if( DGifGetLine( gif->file, gif->line,
if( DGifGetLine( gif->file, gif->line,
file->Image.Width ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
vips_foreign_load_gif_render_line( gif,
file->Image.Width, q, gif->line );
vips_foreign_load_gif_render_line( gif,
file->Image.Width, q, gif->line );
}
}
@ -814,23 +814,23 @@ vips_foreign_load_gif_extension( VipsForeignLoadGif *gif )
GifByteType *extension;
int ext_code;
VIPS_DEBUG_MSG( "vips_foreign_load_gif_extension:\n" );
VIPS_DEBUG_MSG( "vips_foreign_load_gif_extension:\n" );
if( DGifGetExtension( gif->file, &ext_code, &extension ) ==
if( DGifGetExtension( gif->file, &ext_code, &extension ) ==
GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
if( extension &&
ext_code == GRAPHICS_EXT_FUNC_CODE &&
extension[0] == 4 ) {
extension[0] == 4 ) {
/* Bytes are flags, delay low, delay high,
* transparency. Flag bit 1 means transparency
* is being set.
*/
gif->transparency = -1;
if( extension[1] & 0x1 )
if( extension[1] & 0x1 )
gif->transparency = extension[4];
/* Set the current dispose mode. This is read during frame load
@ -838,12 +838,12 @@ vips_foreign_load_gif_extension( VipsForeignLoadGif *gif )
*/
gif->dispose = (extension[1] >> 2) & 0x7;
VIPS_DEBUG_MSG( "vips_foreign_load_gif_extension: "
"dispose = %d\n", gif->dispose );
"dispose = %d\n", gif->dispose );
}
while( extension != NULL )
while( extension != NULL )
if( vips_foreign_load_gif_ext_next( gif, &extension ) )
return( -1 );
return( -1 );
return( 0 );
}
@ -857,24 +857,24 @@ vips_foreign_load_gif_next_page( VipsForeignLoadGif *gif )
gboolean have_read_frame;
have_read_frame = FALSE;
do {
do {
if( DGifGetRecordType( gif->file, &record ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
switch( record ) {
case IMAGE_DESC_RECORD_TYPE:
VIPS_DEBUG_MSG( "vips_foreign_load_gif_next_page: "
"IMAGE_DESC_RECORD_TYPE\n" );
"IMAGE_DESC_RECORD_TYPE\n" );
if( DGifGetImageDesc( gif->file ) == GIF_ERROR ) {
vips_foreign_load_gif_error( gif );
return( -1 );
vips_foreign_load_gif_error( gif );
return( -1 );
}
if( vips_foreign_load_gif_render( gif ) )
return( -1 );
return( -1 );
have_read_frame = TRUE;
@ -887,7 +887,7 @@ vips_foreign_load_gif_next_page( VipsForeignLoadGif *gif )
case TERMINATE_RECORD_TYPE:
VIPS_DEBUG_MSG( "vips_foreign_load_gif_next_page: "
"TERMINATE_RECORD_TYPE\n" );
"TERMINATE_RECORD_TYPE\n" );
gif->eof = TRUE;
break;
@ -911,7 +911,7 @@ vips_foreign_load_gif_next_page( VipsForeignLoadGif *gif )
}
static int
vips_foreign_load_gif_generate( VipsRegion *or,
vips_foreign_load_gif_generate( VipsRegion *or,
void *seq, void *a, void *b, gboolean *stop )
{
VipsRect *r = &or->valid;
@ -931,17 +931,17 @@ vips_foreign_load_gif_generate( VipsRegion *or,
g_assert( line >= 0 && line < gif->frame->Ysize );
g_assert( page >= 0 && page < gif->n_pages );
/* current_page == 0 means we've not loaded any pages yet. So
/* current_page == 0 means we've not loaded any pages yet. So
* we need to have loaded the page beyond the page we want.
*/
while( gif->current_page <= page ) {
if( vips_foreign_load_gif_next_page( gif ) )
return( -1 );
gif->current_page += 1;
gif->current_page += 1;
}
/* @frame is always RGBA, but or may be G, GA, RGB or RGBA.
/* @frame is always RGBA, but or may be G, GA, RGB or RGBA.
* We have to pick out the values we want.
*/
p = VIPS_IMAGE_ADDR( gif->frame, 0, line );
@ -993,10 +993,10 @@ vips_foreign_load_gif_generate( VipsRegion *or,
static int
vips_foreign_load_gif_load( VipsForeignLoad *load )
{
VipsForeignLoadGifClass *class =
VipsForeignLoadGifClass *class =
(VipsForeignLoadGifClass *) VIPS_OBJECT_GET_CLASS( load );
VipsForeignLoadGif *gif = (VipsForeignLoadGif *) load;
VipsImage **t = (VipsImage **)
VipsImage **t = (VipsImage **)
vips_object_local_array( VIPS_OBJECT( load ), 4 );
/* Rewind.
@ -1004,27 +1004,27 @@ vips_foreign_load_gif_load( VipsForeignLoad *load )
if( class->open( gif ) )
return( -1 );
VIPS_DEBUG_MSG( "vips_foreign_load_gif_load:\n" );
VIPS_DEBUG_MSG( "vips_foreign_load_gif_load:\n" );
/* Make the memory image we accumulate pixels in. We always accumulate
* to RGBA, then trim down to whatever the output image needs on
* _generate.
*/
gif->frame = vips_image_new_memory();
vips_image_init_fields( gif->frame,
vips_image_init_fields( gif->frame,
gif->file->SWidth, gif->file->SHeight, 4, VIPS_FORMAT_UCHAR,
VIPS_CODING_NONE, VIPS_INTERPRETATION_sRGB, 1.0, 1.0 );
if( vips_image_write_prepare( gif->frame ) )
if( vips_image_write_prepare( gif->frame ) )
return( -1 );
/* A copy of the previous state of the frame, in case we have to
* process a DISPOSE_PREVIOUS.
*/
gif->previous = vips_image_new_memory();
vips_image_init_fields( gif->previous,
vips_image_init_fields( gif->previous,
gif->file->SWidth, gif->file->SHeight, 4, VIPS_FORMAT_UCHAR,
VIPS_CODING_NONE, VIPS_INTERPRETATION_sRGB, 1.0, 1.0 );
if( vips_image_write_prepare( gif->previous ) )
if( vips_image_write_prepare( gif->previous ) )
return( -1 );
/* Make the output pipeline.
@ -1035,10 +1035,10 @@ vips_foreign_load_gif_load( VipsForeignLoad *load )
/* Strips 8 pixels high to avoid too many tiny regions.
*/
if( vips_image_generate( t[0],
if( vips_image_generate( t[0],
NULL, vips_foreign_load_gif_generate, NULL, gif, NULL ) ||
vips_sequential( t[0], &t[1],
"tile_height", VIPS__FATSTRIP_HEIGHT,
vips_sequential( t[0], &t[1],
"tile_height", VIPS__FATSTRIP_HEIGHT,
NULL ) ||
vips_image_write( t[1], load->real ) )
return( -1 );
@ -1055,13 +1055,13 @@ vips_foreign_load_gif_open( VipsForeignLoadGif *gif )
if( !(gif->file = DGifOpen( gif->userPtr, gif->read_func, &error )) ) {
vips_foreign_load_gif_error_vips( gif, error );
return( -1 );
return( -1 );
}
}
#else
if( !(gif->file = DGifOpen( gif->userPtr, gif->read_func )) ) {
vips_foreign_load_gif_error_vips( gif, GifLastError() );
return( -1 );
#else
if( !(gif->file = DGifOpen( gif->userPtr, gif->read_func )) ) {
vips_foreign_load_gif_error_vips( gif, GifLastError() );
return( -1 );
}
#endif
@ -1070,9 +1070,9 @@ vips_foreign_load_gif_open( VipsForeignLoadGif *gif )
/* Allocate a line buffer now that we have the GIF width.
*/
VIPS_FREE( gif->line )
VIPS_FREE( gif->line )
if( !(gif->line = VIPS_ARRAY( NULL, gif->file->SWidth, GifPixelType )) )
return( -1 );
return( -1 );
return( 0 );
}
@ -1096,7 +1096,7 @@ vips_foreign_load_gif_class_init( VipsForeignLoadGifClass *class )
object_class->nickname = "gifload_base";
object_class->description = _( "load GIF with giflib" );
load_class->get_flags_filename =
load_class->get_flags_filename =
vips_foreign_load_gif_get_flags_filename;
load_class->get_flags = vips_foreign_load_gif_get_flags;
@ -1132,7 +1132,7 @@ typedef struct _VipsForeignLoadGifFile {
/* Filename for load.
*/
char *filename;
char *filename;
/* The FILE* we read from.
*/
@ -1142,7 +1142,7 @@ typedef struct _VipsForeignLoadGifFile {
typedef VipsForeignLoadGifClass VipsForeignLoadGifFileClass;
G_DEFINE_TYPE( VipsForeignLoadGifFile, vips_foreign_load_gif_file,
G_DEFINE_TYPE( VipsForeignLoadGifFile, vips_foreign_load_gif_file,
vips_foreign_load_gif_get_type() );
static void
@ -1150,7 +1150,7 @@ vips_foreign_load_gif_file_dispose( GObject *gobject )
{
VipsForeignLoadGifFile *file = (VipsForeignLoadGifFile *) gobject;
VIPS_FREEF( fclose, file->fp );
VIPS_FREEF( fclose, file->fp );
G_OBJECT_CLASS( vips_foreign_load_gif_file_parent_class )->
dispose( gobject );
@ -1159,9 +1159,9 @@ vips_foreign_load_gif_file_dispose( GObject *gobject )
/* Our input function for file open. We can't use DGifOpenFileName(), since
* that just calls open() and won't work with unicode on win32. We can't use
* DGifOpenFileHandle() since that's an fd from open() and you can't pass those
* across DLL boundaries on Windows.
* across DLL boundaries on Windows.
*/
static int
static int
vips_giflib_file_read( GifFileType *file, GifByteType *buffer, int n )
{
FILE *fp = (FILE *) file->UserData;
@ -1176,20 +1176,20 @@ vips_foreign_load_gif_file_open( VipsForeignLoadGif *gif )
VipsForeignLoadGifFile *file = (VipsForeignLoadGifFile *) gif;
if( !file->fp ) {
if( !(file->fp =
vips__file_open_read( file->filename, NULL, FALSE )) )
return( -1 );
if( !(file->fp =
vips__file_open_read( file->filename, NULL, FALSE )) )
return( -1 );
VIPS_SETSTR( load->out->filename, file->filename );
}
else
else
rewind( file->fp );
vips_foreign_load_gif_close( gif );
gif->userPtr = file->fp;
gif->read_func = vips_giflib_file_read;
return( VIPS_FOREIGN_LOAD_GIF_CLASS(
return( VIPS_FOREIGN_LOAD_GIF_CLASS(
vips_foreign_load_gif_file_parent_class )->open( gif ) );
}
@ -1199,7 +1199,7 @@ static const char *vips_foreign_gif_suffs[] = {
};
static void
vips_foreign_load_gif_file_class_init(
vips_foreign_load_gif_file_class_init(
VipsForeignLoadGifFileClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
@ -1221,10 +1221,10 @@ vips_foreign_load_gif_file_class_init(
gif_class->open = vips_foreign_load_gif_file_open;
VIPS_ARG_STRING( class, "filename", 1,
VIPS_ARG_STRING( class, "filename", 1,
_( "Filename" ),
_( "Filename to load from" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadGifFile, filename ),
NULL );
@ -1251,7 +1251,7 @@ typedef struct _VipsForeignLoadGifBuffer {
typedef VipsForeignLoadGifClass VipsForeignLoadGifBufferClass;
G_DEFINE_TYPE( VipsForeignLoadGifBuffer, vips_foreign_load_gif_buffer,
G_DEFINE_TYPE( VipsForeignLoadGifBuffer, vips_foreign_load_gif_buffer,
vips_foreign_load_gif_get_type() );
/* Callback from the gif loader.
@ -1261,7 +1261,7 @@ G_DEFINE_TYPE( VipsForeignLoadGifBuffer, vips_foreign_load_gif_buffer,
static int
vips_giflib_buffer_read( GifFileType *file, GifByteType *buf, int n )
{
VipsForeignLoadGifBuffer *buffer =
VipsForeignLoadGifBuffer *buffer =
(VipsForeignLoadGifBuffer *) file->UserData;
size_t will_read = VIPS_MIN( n, buffer->bytes_to_go );
@ -1269,7 +1269,7 @@ vips_giflib_buffer_read( GifFileType *file, GifByteType *buf, int n )
buffer->p += will_read;
buffer->bytes_to_go -= will_read;
return( will_read );
return( will_read );
}
static int
@ -1283,12 +1283,12 @@ vips_foreign_load_gif_buffer_open( VipsForeignLoadGif *gif )
gif->userPtr = gif;
gif->read_func = vips_giflib_buffer_read;;
return( VIPS_FOREIGN_LOAD_GIF_CLASS(
return( VIPS_FOREIGN_LOAD_GIF_CLASS(
vips_foreign_load_gif_file_parent_class )->open( gif ) );
}
static void
vips_foreign_load_gif_buffer_class_init(
vips_foreign_load_gif_buffer_class_init(
VipsForeignLoadGifBufferClass *class )
{
GObjectClass *gobject_class = G_OBJECT_CLASS( class );
@ -1306,10 +1306,10 @@ vips_foreign_load_gif_buffer_class_init(
gif_class->open = vips_foreign_load_gif_buffer_open;
VIPS_ARG_BOXED( class, "buffer", 1,
VIPS_ARG_BOXED( class, "buffer", 1,
_( "Buffer" ),
_( "Buffer to load from" ),
VIPS_ARGUMENT_REQUIRED_INPUT,
VIPS_ARGUMENT_REQUIRED_INPUT,
G_STRUCT_OFFSET( VipsForeignLoadGifBuffer, buf ),
VIPS_TYPE_BLOB );
@ -1339,11 +1339,11 @@ vips_foreign_load_gif_buffer_init( VipsForeignLoadGifBuffer *buffer )
*
* Use @n to select the number of pages to render. The default is 1. Pages are
* rendered in a vertical column, with each individual page aligned to the
* left. Set to -1 to mean "until the end of the document". Use vips_grid()
* left. Set to -1 to mean "until the end of the document". Use vips_grid()
* to change page layout.
*
* The whole GIF is rendered into memory on header access. The output image
* will be 1, 2, 3 or 4 bands depending on what the reader finds in the file.
* will be 1, 2, 3 or 4 bands depending on what the reader finds in the file.
*
* See also: vips_image_new_from_file().
*
@ -1375,10 +1375,10 @@ vips_gifload( const char *filename, VipsImage **out, ... )
* * @n: %gint, load this many pages
*
* Read a GIF-formatted memory block into a VIPS image. Exactly as
* vips_gifload(), but read from a memory buffer.
* vips_gifload(), but read from a memory buffer.
*
* You must not free the buffer while @out is active. The
* #VipsObject::postclose signal on @out is a good place to free.
* You must not free the buffer while @out is active. The
* #VipsObject::postclose signal on @out is a good place to free.
*
* See also: vips_gifload().
*

28
libvips/foreign/magicksave.c
View File

@ -6,6 +6,8 @@
* 17/2/19
* - support ICC, XMP, EXIF, IPTC metadata
* - write with a single call to vips_sink_disc()
* 29/6/19
* - support "strip" option
*/
/*
@ -68,6 +70,8 @@ typedef struct _VipsForeignSaveMagick {
Image *current_image;
int page_height;
int *delays;
int delays_length;
/* The position of current_image in the output.
*/
@ -109,9 +113,8 @@ vips_foreign_save_magick_next_image( VipsForeignSaveMagick *magick )
Image *image;
int number;
int *numbers;
int numbers_length;
const char *str;
int page_index;
g_assert( !magick->current_image );
@ -141,11 +144,13 @@ vips_foreign_save_magick_next_image( VipsForeignSaveMagick *magick )
im->Xsize, magick->page_height, magick->exception ) )
return( -1 );
if( vips_image_get_typeof( im, "delay" ) &&
!vips_image_get_array_int( im, "delay", &numbers, &numbers_length ) ) {
int page_index = magick->position.top / magick->page_height;
if( page_index < numbers_length )
image->delay = (size_t) VIPS_RINT( numbers[page_index] / 10.0 );
/* Delay must be converted from milliseconds into centiseconds
* as GIF image requires centiseconds.
*/
if ( magick->delays != NULL) {
page_index = magick->position.top / magick->page_height;
if( page_index < magick->delays_length )
image->delay = (size_t) VIPS_RINT( magick->delays[page_index] / 10.0 );
}
/* ImageMagick uses iterations like this (at least in gif save):
@ -170,7 +175,8 @@ vips_foreign_save_magick_next_image( VipsForeignSaveMagick *magick )
*/
image->dispose = BackgroundDispose;
if( magick_set_magick_profile( image, im, magick->exception ) ) {
if( !save->strip &&
magick_set_magick_profile( image, im, magick->exception ) ) {
magick_vips_error( class->nickname, magick->exception );
return( -1 );
}
@ -340,6 +346,12 @@ vips_foreign_save_magick_build( VipsObject *object )
magick->page_height = vips_image_get_page_height( im );
if( vips_image_get_typeof( im, "delay" ) &&
vips_image_get_array_int( im,
"delay", &magick->delays, &magick->delays_length ) ) {
return( -1 );
}
if( vips_sink_disc( im,
vips_foreign_save_magick_write_block, magick ) )
return( -1 );

6
libvips/foreign/vips2webp.c
View File

@ -308,7 +308,8 @@ get_array_int( VipsImage *image, const char *field, int* n )
static int
extract_delay( int index, int *delays, int delays_length, int default_delay )
{
if( delays == NULL || index > delays_length ) return( default_delay );
if( delays == NULL || index > delays_length )
return( default_delay );
return( delays[index] );
}
@ -351,6 +352,7 @@ write_webp_anim( VipsWebPWrite *write, VipsImage *image, int page_height )
for( top = 0; top < image->Ysize; top += page_height ) {
VipsImage *x;
WebPPicture pic;
int page_index;
if( vips_crop( image, &x,
0, top, image->Xsize, page_height, NULL ) )
@ -373,7 +375,7 @@ write_webp_anim( VipsWebPWrite *write, VipsImage *image, int page_height )
WebPPictureFree( &pic );
int page_index = top / page_height;
page_index = top / page_height;
timestamp_ms += extract_delay( page_index, delays, delays_length, default_delay );
}

114
libvips/foreign/webp2vips.c
View File

@ -20,6 +20,8 @@
* 30/4/19
* - deprecate shrink, use scale instead, and make it a double ... this
* lets us do faster and more accurate thumbnailing
* 27/6/19
* - disable alpha output if all frame fill the canvas and are solid
*/
/*
@ -97,17 +99,22 @@ typedef struct {
*/
double scale;
/* Size of each frame in input image coordinates.
*/
int canvas_width;
int canvas_height;
/* Size of each frame, in scaled output image coordinates,
*/
int frame_width;
int frame_height;
/* Size of final output image.
*/
int width;
int height;
/* Size of each frame.
*/
int frame_width;
int frame_height;
/* TRUE for RGBA.
/* TRUE if we will save the final image as RGBA.
*/
int alpha;
@ -280,11 +287,6 @@ vips_image_paint_image( VipsImage *frame,
g_assert( VIPS_IMAGE_SIZEOF_PEL( sub ) == ps );
/* Disable blend if we are not RGBA.
*/
if( frame->Bands != 4 )
blend = FALSE;
vips_rect_intersectrect( &frame_rect, &sub_rect, &ovl );
if( !vips_rect_isempty( &ovl ) ) {
VipsPel *p, *q;
@ -356,6 +358,7 @@ read_free( Read *read )
VIPS_FREEF( vips_tracked_close, read->fd );
VIPS_FREE( read->filename );
VIPS_FREE( read->delays );
VIPS_FREE( read );
return( 0 );
@ -418,8 +421,6 @@ static int
read_header( Read *read, VipsImage *out )
{
WebPData data;
int canvas_width;
int canvas_height;
int flags;
int i;
@ -430,16 +431,19 @@ read_header( Read *read, VipsImage *out )
return( -1 );
}
canvas_width = WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_WIDTH );
canvas_height = WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_HEIGHT );
read->canvas_width =
WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_WIDTH );
read->canvas_height =
WebPDemuxGetI( read->demux, WEBP_FF_CANVAS_HEIGHT );
/* We round-to-nearest cf. pdfload etc.
*/
read->frame_width = VIPS_RINT( canvas_width * read->scale );
read->frame_height = VIPS_RINT( canvas_height * read->scale );
read->frame_width = VIPS_RINT( read->canvas_width * read->scale );
read->frame_height = VIPS_RINT( read->canvas_height * read->scale );
#ifdef DEBUG
printf( "webp2vips: canvas_width = %d\n", canvas_width );
printf( "webp2vips: canvas_height = %d\n", canvas_height );
printf( "webp2vips: canvas_width = %d\n", read->canvas_width );
printf( "webp2vips: canvas_height = %d\n", read->canvas_height );
printf( "webp2vips: frame_width = %d\n", read->frame_width );
printf( "webp2vips: frame_height = %d\n", read->frame_height );
#endif /*DEBUG*/
@ -447,10 +451,11 @@ read_header( Read *read, VipsImage *out )
flags = WebPDemuxGetI( read->demux, WEBP_FF_FORMAT_FLAGS );
read->alpha = flags & ALPHA_FLAG;
if( read->alpha )
read->config.output.colorspace = MODE_RGBA;
else
read->config.output.colorspace = MODE_RGB;
/* We do everything as RGBA and then, if we can, drop the alpha on
* save.
*/
read->config.output.colorspace = MODE_RGBA;
if( flags & ANIMATION_FLAG ) {
int loop_count;
@ -471,29 +476,39 @@ read_header( Read *read, VipsImage *out )
VIPS_META_PAGE_HEIGHT, read->frame_height );
if ( read->frame_count > 1) {
read->delays = (int *) g_malloc( read->frame_count * sizeof(int) );
int i;
read->delays = (int *) g_malloc0( read->frame_count * sizeof(int) );
for( int i = 0; i < read->frame_count; i++ ) {
if( WebPDemuxGetFrame( read->demux, i + 1, &iter ) ) {
for( i = 0; i < read->frame_count; i++ ) {
if( WebPDemuxGetFrame( read->demux, i + 1, &iter ) )
read->delays[i] = iter.duration;
} else {
read->delays[i] = 0;
}
}
#ifdef DEBUG
for( int i = 0; i < read->frame_count; i++ ) {
for( i = 0; i < read->frame_count; i++ ) {
printf( "webp2vips: frame = %d; duration = %d\n", i + 1, read->delays[i] );
}
#endif /*DEBUG*/
vips_image_set_array_int( out, "delay", read->delays, read->frame_count );
g_free( read->delays );
/* webp uses ms for delays, gif uses centiseconds.
*/
vips_image_set_int( out, "gif-delay",
VIPS_RINT( read->delays[0] / 10.0 ) );
VIPS_RINT( read->delays[0] / 10.0 ) );
/* We need the alpha in an animation if:
* - any frame has transparent pixels
* - any frame doesn't fill the whole canvas.
*/
do {
if( iter.has_alpha ||
iter.width != read->canvas_width ||
iter.height != read->canvas_height ) {
read->alpha = TRUE;
break;
}
} while( WebPDemuxNextFrame( &iter ) );
}
WebPDemuxReleaseIterator( &iter );
@ -543,10 +558,12 @@ read_header( Read *read, VipsImage *out )
}
}
/* The canvas is always RGBA, we drop alpha to RGB on output if we
* can.
*/
read->frame = vips_image_new_memory();
vips_image_init_fields( read->frame,
read->frame_width, read->frame_height,
read->alpha ? 4 : 3,
read->frame_width, read->frame_height, 4,
VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
VIPS_INTERPRETATION_sRGB,
1.0, 1.0 );
@ -609,8 +626,7 @@ read_frame( Read *read,
frame = vips_image_new_memory();
vips_image_init_fields( frame,
width, height,
read->alpha ? 4 : 3,
width, height, 4,
VIPS_FORMAT_UCHAR, VIPS_CODING_NONE,
VIPS_INTERPRETATION_sRGB,
1.0, 1.0 );
@ -750,9 +766,29 @@ read_webp_generate( VipsRegion *or,
read->frame_no += 1;
}
memcpy( VIPS_REGION_ADDR( or, 0, r->top ),
VIPS_IMAGE_ADDR( read->frame, 0, line ),
VIPS_IMAGE_SIZEOF_LINE( read->frame ) );
if( or->im->Bands == 4 )
memcpy( VIPS_REGION_ADDR( or, 0, r->top ),
VIPS_IMAGE_ADDR( read->frame, 0, line ),
VIPS_IMAGE_SIZEOF_LINE( read->frame ) );
else {
int x;
VipsPel *p;
VipsPel *q;
/* We know that alpha is solid, so we can just drop the 4th
* band.
*/
p = VIPS_IMAGE_ADDR( read->frame, 0, line );
q = VIPS_REGION_ADDR( or, 0, r->top );
for( x = 0; x < r->width; x++ ) {
q[0] = p[0];
q[1] = p[1];
q[2] = p[2];
q += 3;
p += 4;
}
}
return( 0 );
}

4
test/test-suite/test_foreign.py
View File

@ -463,7 +463,7 @@ class TestForeign:
def test_webp(self):
def webp_valid(im):
a = im(10, 10)
assert_almost_equal_objects(a, [71, 166, 236])
assert_almost_equal_objects(a, [70, 165, 235])
assert im.width == 550
assert im.height == 368
assert im.bands == 3
@ -478,7 +478,7 @@ class TestForeign:
im = pyvips.Image.new_from_file(WEBP_FILE)
buf = im.webpsave_buffer(lossless=True)
im2 = pyvips.Image.new_from_buffer(buf, "")
assert im.avg() == im2.avg()
assert abs(im.avg() - im2.avg()) < 1
# higher Q should mean a bigger buffer
b1 = im.webpsave_buffer(Q=10)