Image processing circuit, and display panel driver and display device mounting the circuit

• US 8,385,668 B2
• Filed: 01/31/2012
• Issued: 02/26/2013
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Synaptics Japan GK (Synaptics Incorporated)
• Original Assignee: Renesas Electronics Corporation
• Inventors: Furihata, Hirobumi, Nose, Takashi
• Primary Examiner(s): Bella, Matthew
• Assistant Examiner(s): RASHIDIAN, MOHAMMAD M
• Application Number:
  US13/363,308
• Publication Number:
  US 20120127188A1
• Time in Patent Office: 392 Days
• Field of Search: 382/100, 382162-167, 382/197, 382199-200, 382/203, 382232-253, 382266-268, 382/270, 382/272, 382274-275, 382283-284, 382/298, 382/307, 375/E7.088, 375/E7.133, 37524001-24025, 712/1, 712/200, 709/203, 709/236, 358/1.18, 358/1.9, 358/1.2, 358/2.1, 358 313- 322, 358/450, 358/452, 358/500, 358/521, 358/539, 345/1.1, 345/204, 345/501, 345/537, 345/556, 345/560, 345/572, 345/589, 345/597, 345/602, 345/604
• US Class Current: 382/244
• CPC Class Codes: G06T 9/00 Image coding bandwidth or redundancy reduction for static pictures H04N1/41; coding or decoding of static colour picture signals H04N1/64; methods or arrangements for coding, decoding, compressing or decompressing digital video signals H04N19/00
• CPC Class Codes: G09G 2340/02 Handling of images in compressed format, e.g. JPEG, MPEG
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H04N 19/12 Selection from among a plurality of transforms or standards, e.g. selection between discrete cosine transform [DCT] and sub-band transform or selection between H.263 and H.264
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/186 the unit being a colour or a chrominance component

Abstract

A display panel driver includes a compression circuit configured to, when receiving image data of a plurality of pixels of a target block, generate compressed image data corresponding to the target block by compressing the image data, an image memory configured to store the compressed image data, a decompression circuit configured to generate decompressed image data by decompressing the compressed image data reading from the image memory, and a drive circuit configured to drive a display panel in response to the decompressed image data. The number of bits of the compression type recognition bit of the compressed image data becomes low, when the correlation between the image data of the plurality of pixels becomes low.

Claims

1. A display panel driver comprising:

a compression circuit configured to, when receiving image data of a plurality of pixels of a target block, generate compressed image data corresponding to said target block by compressing said image data;

an image memory configured to store said compressed image data;

a decompression circuit configured to generate decompressed image data by decompressing said compressed image data reading from said image memory; and

a drive circuit configured to drive a display panel in response to said decompressed image data,

wherein said compression circuit selects one of a plurality of compression methods based on a correlation between said image data of said plurality of pixels of said target block, and generates said compressed image data by using said selected compression method,

wherein the number of bits of said compressed image data is constant regardless of said plurality of compression methods,

wherein said compressed image data includes a compression type recognition bit indicating a type of said selected compression method, and

wherein the number of bits of said compression type recognition bit of said compressed image data becomes low, when said correlation between said image data of said plurality of pixels becomes low.

2. A display device comprising:

a display panel; and

a display panel driver configured to drive said display panel,

wherein said display panel driver includes;

a compression circuit configured to, when receiving image data of a plurality of pixels of a target block, generate compressed image data corresponding to said target block by compressing said image data,

an image memory configured to store said compressed image data,

a decompression circuit configured to generate decompressed image data by decompressing said compressed image data reading from said image memory, and

a drive circuit configured to drive a display panel in response to said decompressed image data,

wherein said compression circuit selects one of a plurality of compression methods based on a correlation between said image data of said plurality of pixels of said target block, and generates said compressed image data by using said selected compression method,

wherein the number of bits of said compressed image data is constant regardless of said plurality of compression methods,

wherein said compressed image data includes a compression type recognition bit indicating a type of said selected compression method, and

wherein the number of bits of said compression type recognition bit of said compressed image data becomes low, when said correlation between said image data of said plurality of pixels becomes low.

3. An image processing circuit comprising:

a compression circuit configured to, when receiving image data of a plurality of pixels of a target block, generate compressed image data corresponding to said target block by compressing said image data,

wherein said compression circuit selects one of a plurality of compression methods based on a correlation between said image data of said plurality of pixels of said target block, and generates said compressed image data by using said selected compression method,

wherein the number of bits of said compressed image data is constant regardless of said plurality of compression methods,

wherein said compressed image data includes a compression type recognition bit indicating a type of said selected compression method, and

wherein the number of bits of said compression type recognition bit of said compressed image data becomes low, when said correlation between said image data of said plurality of pixels becomes low.