When you are reducing the size of the image, it means the no of pixel in an image is reduced so the image quality is also reduced. But there are different way by which you reduce the number of pixels, like simple sampling, using bilinear transformation, bicubic, etc which means, in a simple way the new pixels represents an values of the discarded pixels also. Thus the photo might look more good. The photoshop, Matlab gives these options of how to resize an image. Iam sure that simple userfriendly programs are there in Linux, but I dont know the names of the programs.
Dr. Reji On Thu, Mar 18, 2010 at 10:04 PM, Anoop Alias <[email protected]> wrote: > Hey, > > Given stamp size is lesser than passport.you can resize the image in GIMP > without any quality loss . I think GIMP pops the option to select the > quality when you try to save the image. Drag the slider to 100 % :) > > If you are not gonna do it in a batch mode for many images;I would suggest > GIMP is the easier path > > On Thu, Mar 18, 2010 at 9:42 PM, sanalkumar mr <[email protected]> > wrote: >> >> Does anybody think that the pixel values for a stamp size image given here >> enough to get the quality image.? Can pixel values be replaced with 1.8cm >> x1.3 cm ie stamp size? In other words 51x37 with 1.8cm x 1.3 cm ? Any idea? >> Thanks in advance....sanal >> - Show quoted text - >> >> On Thu, Mar 18, 2010 at 9:25 PM, sanalkumar mr <[email protected]> >> wrote: >>> >>> But still the quality comparatively very less.....What may be the reason? >>> Any idea?..sanal >>> >>> On Thu, Mar 18, 2010 at 9:19 PM, sanalkumar mr <[email protected]> >>> wrote: >>>> >>>> Dear Jos Collin...Thanks a lot for your timely support..sanal (I'll try >>>> it) >>>> >>>> On Thu, Mar 18, 2010 at 8:11 PM, Jos Collin <[email protected]> wrote: >>>>> >>>>> On Thu, Mar 18, 2010 at 07:02:24PM +0530, Jos Collin wrote: >>>>> > On Thu, Mar 18, 2010 at 06:48:04PM +0530, Jos Collin wrote: >>>>> > > On Thu, Mar 18, 2010 at 06:31:53PM +0530, sanalkumar mr wrote: >>>>> > > > Dear all......I' ve to convert a passport size photo to stamp >>>>> > > > size. I tried >>>>> > > > $ convert -resize 51x37 sanal.jpg san.JPEG >>>>> > > > giving a low quality image.Any option to get a good quality >>>>> > > > image...? >>>>> > > > And the properties of the input image is given below >>>>> > > > $ identify sanal.jpg >>>>> > > > sanal.jpg JPEG 260x300 260x300+0+0 DirectClass 8-bit 35.0488kb >>>>> > > > I also tried GIMP that also was in vain.Thanks in >>>>> > > > advance....Sanalkumar >>>>> > > > -- >>>>> > > >>>>> > > Hello Sir, >>>>> > > >>>>> > > I believe that the option -quality is what you need. >>>>> > > $convert -resize 51x37 -quality 80% sanal.jpg san.JPEG >>>>> > > This will retain 80% picture quality. >>>>> > > >>>>> > >>>>> > I'm sorry. I don't know whether -quality will increase or decrease >>>>> > the >>>>> > compression level. I think by adjusting the value (percentage) you >>>>> > can >>>>> > solve your problem. >>>>> > >>>>> >>>>> I have verified that the following gives the maximum picture quality. >>>>> $convert -resize 51x37 -quality 100% sanal.jpg san.JPEG >>>>> >>>>> _______________________________________________ >>>>> Indian Libre User Group Cochin Mailing List >>>>> http://www.ilug-cochin.org/mailing-list/ >>>>> >>>>> http://mail.ilug-cochin.org/mailman/listinfo/mailinglist_ilug-cochin.org >>>>> #[email protected] >>>> >>>> >>>> >>>> -- >>>> പറയാതെ പരിഭവം നീയൊന്നു മുടി കോതി- >>>> ക്കഴിയുമ്പൊഴായുസ്സു തീരും >>>> പറയാതെ പരിഭവം ഞാനൊന്നു നെടുവീര്പ്പിട്ടു- >>>> കഴിയുമ്പോള് ലോകവും തീരും.......... >>> >>> >>> >>> -- >>> പറയാതെ പരിഭവം നീയൊന്നു മുടി കോതി- >>> ക്കഴിയുമ്പൊഴായുസ്സു തീരും >>> പറയാതെ പരിഭവം ഞാനൊന്നു നെടുവീര്പ്പിട്ടു- >>> കഴിയുമ്പോള് ലോകവും തീരും.......... >> >> >> >> -- >> പറയാതെ പരിഭവം നീയൊന്നു മുടി കോതി- >> ക്കഴിയുമ്പൊഴായുസ്സു തീരും >> പറയാതെ പരിഭവം ഞാനൊന്നു നെടുവീര്പ്പിട്ടു- >> കഴിയുമ്പോള് ലോകവും തീരും.......... >> >> _______________________________________________ >> Indian Libre User Group Cochin Mailing List >> http://www.ilug-cochin.org/mailing-list/ >> http://mail.ilug-cochin.org/mailman/listinfo/mailinglist_ilug-cochin.org >> #[email protected] > > > > -- > Anoop P Alias (PGP Key ID : 0x014F9953) > GNU system administrator > http://GnuSys.net > > _______________________________________________ > Indian Libre User Group Cochin Mailing List > http://www.ilug-cochin.org/mailing-list/ > http://mail.ilug-cochin.org/mailman/listinfo/mailinglist_ilug-cochin.org > #[email protected] > _______________________________________________ Indian Libre User Group Cochin Mailing List http://www.ilug-cochin.org/mailing-list/ http://mail.ilug-cochin.org/mailman/listinfo/mailinglist_ilug-cochin.org #[email protected]
