Search found 8 matches

by jasonlee
2013-07-16T19:08:22-07:00
Forum: Bugs
Topic: Possible bug with memory release
Replies: 1
Views: 1886

Possible bug with memory release

Hello There, I have followings: SELS 10.04 64 bit Nginx nginx 0.8.20 ImageMagick version: ImageMagick 6.7.8 I wrote an image compressing module of nginx with imagemagick, but now I encounterer with an error: 1. the temp directory is filled with image magick dumpped files such as: -rw------- 1 root r...
by jasonlee
2013-07-01T19:16:55-07:00
Forum: Developers
Topic: how to get depth of png files
Replies: 4
Views: 5621

Re: how to get depth of png files

fmw42 wrote:Sorry I cannot help. I do not use any API just the command line.

Thank you all the same.
by jasonlee
2013-06-30T23:29:52-07:00
Forum: Developers
Topic: how to get depth of png files
Replies: 4
Views: 5621

Re: how to get depth of png files

fmw42 wrote:depth is per channel, so multiply by the number of channels

Thanks. But I get zero as number of channels. As i got code:

Code: Select all

printf("thumbnails->channels=%d\n", (int)thumbnails->channels);
Thanks for your clearation.
by jasonlee
2013-06-30T20:28:35-07:00
Forum: Developers
Topic: how to get depth of png files
Replies: 4
Views: 5621

how to get depth of png files

I'm using MagickCore to get depth of png files, (Version ImageMagick-6.7.8 ) but it doesnot work correctly, I have 32-bit and a 8-bit png pictures, but im tells them depth are same as 8-bit, it's so strange. Image *images = NULL, *thumbnails = NULL; ngx_buf_t* buf = NULL; size_t len; u_char *inputbl...
by jasonlee
2013-06-27T01:00:11-07:00
Forum: Developers
Topic: Can not change depth of png files
Replies: 2
Views: 3832

Re: Can not change depth of png files

Crap, your completely right. I add such code: QuantizeInfo *q_info = AcquireQuantizeInfo( image_info ); q_info->number_colors=256; q_info->dither = MagickFalse; QuantizeImage(q_info, thumbnails); it all makes sense now. I wasted so much time trying to figure this out. Thanks a lot.
by jasonlee
2013-06-25T19:27:27-07:00
Forum: Developers
Topic: Can not change depth of png files
Replies: 2
Views: 3832

Can not change depth of png files

I'm using MagickCore to convert images from 24bit to 8bit (Version ImageMagick-6.7.8 ), but it doesnot work. And I've got code : Image *images = NULL, *thumbnails = NULL; ngx_buf_t* buf = NULL; size_t len; u_char *inputblob = NULL, *outputblob = NULL; ImageInfo *image_info = NULL; ExceptionInfo *exc...
by jasonlee
2012-12-02T19:25:13-07:00
Forum: Users
Topic: lossy compression or lossless compression?
Replies: 5
Views: 12159

Re: lossy compression or lossless compression?

Any conversion to jpg, even with -quality 100, will cause some loss of quality. JPG is a lossy compression format. If you want lossless, then you could use JP2000. Thanks. But I want to make sure wether it will cause some loss of quality to convert to png or gif. Othermore, wether there are some lo...
by jasonlee
2012-11-29T01:34:27-07:00
Forum: Users
Topic: lossy compression or lossless compression?
Replies: 5
Views: 12159

lossy compression or lossless compression?

Q1: When using ResizeImage() func, will there be quality loss? Q2: When convert an image from png(or gif) format to jpg format, can it cause some question about quality loss? IM Version: ImageMagick 6.7.8-3 2012-09-11 Q16 MagickCore API Q1: Image *zoomimage = ResizeImage(image, width, height, Lanczo...