From 0a2ef6e8c5f910d0f3915feb771bed9119e3fe1c Mon Sep 17 00:00:00 2001 From: John Cupitt Date: Sun, 1 May 2011 11:02:31 +0100 Subject: [PATCH] bufjpeg2vips has a header_only param im_bufjpeg2vips() has header_only, meaning just read width/height/etc. --- ChangeLog | 1 + libvips/format/im_jpeg2vips.c | 171 +++++++++++++++++----------------- libvips/include/vips/format.h | 2 +- 3 files changed, 87 insertions(+), 87 deletions(-) diff --git a/ChangeLog b/ChangeLog index 19ae176d..ad156c13 100644 --- a/ChangeLog +++ b/ChangeLog @@ -52,6 +52,7 @@ - added im_bufjpeg2vips() - tiff reader can do 1, 2, 4, 8 bit palette images - tiff palette read can do mono images +- im_bufjpeg2vips() has a "header_only" parameter 30/11/10 started 7.24.0 - bump for new stable diff --git a/libvips/format/im_jpeg2vips.c b/libvips/format/im_jpeg2vips.c index 99b1aa19..3033f0e4 100644 --- a/libvips/format/im_jpeg2vips.c +++ b/libvips/format/im_jpeg2vips.c @@ -754,6 +754,72 @@ jpeg2vips( const char *name, IMAGE *out, gboolean header_only ) return( result ); } +/** + * im_jpeg2vips: + * @filename: file to load + * @out: image to write to + * + * Read a JPEG file into a VIPS image. It can read most 8-bit JPEG images, + * including CMYK and YCbCr. + * + * You can embed options in the filename. They have the form: + * + * |[ + * filename.jpg:shrink-factor,fail + * ]| + * + * + * + * + * shrink-factor + * Shrink by this integer factor during load. Allowed values are 1, 2, 4 + * and 8. Shrinking during read is very much faster than decompressing the + * whole image and then shrinking. + * + * + * + * + * fail + * This makes the JPEG reader fail on any warnings. This can be useful for + * detecting truncated files, for example. Normally reading these produces + * a warning, but no fatal error. + * + * + * + * + * Example: + * + * |[ + * im_jpeg2vips( "fred.jpg:8" out ); + * im_jpeg2vips( "fred.jpg:,fail" out ); + * ]| + * + * The first example will shrink by a factor of 8 during load. The second will + * fail with an error if there are any problems loading the file. + * + * Any embedded ICC profiles are ignored: you always just get the RGB from + * the file. Instead, the embedded profile will be attached to the image as + * metadata. You need to use something like im_icc_import() to get CIE + * values from the file. Any EXIF data is also attached as VIPS metadata. + * + * The int metadata item "jpeg-multiscan" is set to the result of + * jpeg_has_multiple_scans(). Interlaced jpeg images need a large amount of + * memory to load, so this field gives callers a chance to handle these + * images differently. + * + * The EXIF thumbnail, if present, is attached to the image as + * "jpeg-thumbnail-data". See im_meta_get_blob(). + * + * See also: #VipsFormat, im_vips2jpeg(). + * + * Returns: 0 on success, -1 on error. + */ +int +im_jpeg2vips( const char *filename, IMAGE *out ) +{ + return( jpeg2vips( filename, out, FALSE ) ); +} + /* Just like the above, but we read from a memory buffer. */ typedef struct { @@ -926,10 +992,24 @@ buf_source (j_decompress_ptr cinfo, void *buf, size_t len) src->pub.next_input_byte = NULL; /* until buffer loaded */ } -/* Read a JPEG memory buffer into a VIPS image. +/** + * im_bufjpeg2vips: + * @buf: memory area to load + * @len: size of memory area + * @out: image to write + * @header_only: set to just read the header + * + * Read a JPEG-formatted memory block into a VIPS image. It can read most + * 8-bit JPEG images, including CMYK and YCbCr. + * + * This function is handy for processing JPEG image thumbnails. + * + * See also: #VipsFormat, im_jpeg2vips(). + * + * Returns: 0 on success, -1 on error. */ -static int -bufjpeg2vips( void *buf, size_t len, IMAGE *out, gboolean header_only ) +int +im_bufjpeg2vips( void *buf, size_t len, IMAGE *out, gboolean header_only ) { struct jpeg_decompress_struct cinfo; ErrorManager eman; @@ -973,91 +1053,10 @@ bufjpeg2vips( void *buf, size_t len, IMAGE *out, gboolean header_only ) return( result ); } -/** - * im_jpeg2vips: - * @filename: file to load - * @out: image to write to - * - * Read a JPEG file into a VIPS image. It can read most 8-bit JPEG images, - * including CMYK and YCbCr. - * - * You can embed options in the filename. They have the form: - * - * |[ - * filename.jpg:shrink-factor,fail - * ]| - * - * - * - * - * shrink-factor - * Shrink by this integer factor during load. Allowed values are 1, 2, 4 - * and 8. Shrinking during read is very much faster than decompressing the - * whole image and then shrinking. - * - * - * - * - * fail - * This makes the JPEG reader fail on any warnings. This can be useful for - * detecting truncated files, for example. Normally reading these produces - * a warning, but no fatal error. - * - * - * - * - * Example: - * - * |[ - * im_jpeg2vips( "fred.jpg:8" out ); - * im_jpeg2vips( "fred.jpg:,fail" out ); - * ]| - * - * The first example will shrink by a factor of 8 during load. The second will - * fail with an error if there are any problems loading the file. - * - * Any embedded ICC profiles are ignored: you always just get the RGB from - * the file. Instead, the embedded profile will be attached to the image as - * metadata. You need to use something like im_icc_import() to get CIE - * values from the file. Any EXIF data is also attached as VIPS metadata. - * - * The int metadata item "jpeg-multiscan" is set to the result of - * jpeg_has_multiple_scans(). Interlaced jpeg images need a large amount of - * memory to load, so this field gives callers a chance to handle these - * images differently. - * - * The EXIF thumbnail, if present, is attached to the image as - * "jpeg-thumbnail-data". See im_meta_get_blob(). - * - * See also: #VipsFormat, im_vips2jpeg(). - * - * Returns: 0 on success, -1 on error. - */ int -im_jpeg2vips( const char *filename, IMAGE *out ) +jpeg2vips_header( const char *name, IMAGE *out ) { - return( jpeg2vips( filename, out, FALSE ) ); -} - -/** - * im_bufjpeg2vips: - * @buf: memory area to load - * @len: size of memory area - * @out: image to write - * - * Read a JPEG-formatted memory block into a VIPS image. It can read most - * 8-bit JPEG images, including CMYK and YCbCr. - * - * This function is handy for processing JPEG image thumbnails. - * - * See also: #VipsFormat, im_jpeg2vips(). - * - * Returns: 0 on success, -1 on error. - */ -int -im_bufjpeg2vips( void *buf, size_t len, IMAGE *out ) -{ - return( bufjpeg2vips( buf, len, out, FALSE ) ); + return( jpeg2vips( name, out, TRUE ) ); } static int diff --git a/libvips/include/vips/format.h b/libvips/include/vips/format.h index 7719ed1d..6e17fb35 100644 --- a/libvips/include/vips/format.h +++ b/libvips/include/vips/format.h @@ -123,7 +123,7 @@ int vips_format_write( VipsImage *in, const char *filename ); /* Low-level read/write operations. */ int im_jpeg2vips( const char *filename, VipsImage *out ); -int im_bufjpeg2vips( void *buf, size_t len, VipsImage *out ); +int im_bufjpeg2vips( void *buf, size_t len, IMAGE *out, gboolean header_only ); int im_vips2jpeg( VipsImage *in, const char *filename ); int im_vips2mimejpeg( VipsImage *in, int qfac ); int im_vips2bufjpeg( VipsImage *in, VipsImage *out, int qfac, char **obuf, int *olen );