The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 2009
Filed:
Sep. 02, 2005
Stewart G. Smith, Edinburgh, GB;
Arcangelo Ranieri Bruna, San Cataldo, IT;
Filippo Vella, Casa Santa Erice, IT;
Stewart G. Smith, Edinburgh, GB;
Arcangelo Ranieri Bruna, San Cataldo, IT;
Filippo Vella, Casa Santa Erice, IT;
STMicroelectronics S.r.l., Agrate Brianza (MI), IT;
STMicroelectronics Ltd., Almondsbury, Bristol, GB;
Abstract
A method for image compression of a set of image data includes performing a quantization operation on the image data. The quantization operation may include controlling a compression factor by applying a scaled quantization level obtained by multiplying a first quantization level by a gain factor. The gain factor may be updated as a function of a bit per pixel value of a compressed image. The update operation may include an iterative procedure including at least one iteration step that provides for updating a current gain factor as a function of a previous gain used for performing a previous compression step and as a function of a ratio of the bit per pixel value of the compressed image at the previous compression step to a target bit per pixel value. The method may be used in Joint Photographic Experts Group (JPEG) image processing and digital still cameras.