Image signal processing apparatus

Abstract

An object of this invention is to effectively reduce a luminance flicker caused by noise while suppressing an adverse effect such as an afterimage and a decrease in the resolution upon smoothing as much as possible even when the S/N ratio of an image photographed at an increased gain is low. An image signal processing apparatus includes a smoothing circuit ( 124 ) to execute smoothing processing of an image signal, a compression encoding circuit ( 112, 113 ) to compression-encode the image signal, a setting circuit ( 126 ) capable of setting, for the compression encoding circuit, the code amount for each picture type, and a control circuit ( 116 ) that controls in accordance with a gain setting value acquired from a camera ( 102 ) to change the intensity of smoothing processing and the assignment ratio of code amount for each picture type.

1 .- 21 . (canceled) 
     
     
         22 . An image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, comprising:
 an acquisition unit configured to acquire a gain setting value for the image signal;   a smoothing unit configured to execute smoothing processing of the image signal;   a compression encoding unit, provided on a subsequent stage of said smoothing unit, configured to execute compression-encoding of the image signal;   a setting unit configured to set code amounts to be respectively assigned to each picture type to said compression encoding unit; and   a control unit configured to change an intensity of the smoothing processing by said smoothing unit and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition unit,   wherein said control unit increases the intensity of the smoothing processing by said smoothing unit, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.   
     
     
         23 . The image signal processing apparatus according to  claim 22 , wherein the assignment ratio is changed by changing a ratio of a quantization scale representation value for the picture to be intra-encoded to a quantization scale representation value for the picture to be encoded by inter-picture prediction. 
     
     
         24 . The image signal processing apparatus according to  claim 22 , wherein said smoothing unit executes spatial smoothing processing, temporal smoothing processing, or smoothing processing of both types. 
     
     
         25 . The image signal processing apparatus according to  claim 22 , further comprising a camera unit configured to generate the image signal by photographing, said camera unit having an arrangement to execute gain adjustment of the generated image signal and output the gain setting value, wherein said acquisition unit acquires the gain setting value output from said camera unit. 
     
     
         26 . An image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, comprising:
 an acquisition unit configured to acquire a gain setting value for the image signal and a sharpness setting value for the image signal;   a smoothing unit configured to execute smoothing processing of the image signal;   a compression encoding unit, provided on a subsequent stage of said smoothing unit, configured to execute compression-encoding of the image signal;   an setting unit configured to set code amounts to be respectively assigned to each picture type to said compression encoding unit; and   a control unit configured to control an intensity of the smoothing processing by said smoothing unit and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value and the sharpness setting value acquired by said acquisition unit.   
     
     
         27 . The image signal processing apparatus according to  claims 26 , wherein said control unit increases the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction, when the gain setting value is larger than a predetermined value defined by the sharpness setting value. 
     
     
         28 . The image signal processing apparatus according to  claims 26 , wherein said control unit changes the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, in proportion to the gain setting value at a rate defined by the sharpness setting value. 
     
     
         29 . The image signal processing apparatus according to  claim 26 , wherein said control unit executes the smoothing processing of the image signal when the gain setting value is larger than a predetermined value defined by the sharpness setting value. 
     
     
         30 . The image signal processing apparatus according to  claim 26 , wherein said control unit changes an intensity of the smoothing processing in proportion to the gain setting value at a rate defined by the sharpness setting value. 
     
     
         31 . The image signal processing apparatus according to  claim 26 , further comprising a camera unit configured to generate the image signal by photographing, said camera unit having an arrangement to execute gain adjustment and sharpness adjustment of the generated image signal and output the gain setting value and the sharpness setting value,
 wherein said acquisition unit acquires the gain setting value and the sharpness setting value output from said camera unit.   
     
     
         32 . An image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, comprising:
 an acquisition unit configured to acquire a gain setting value for the image signal;   a smoothing unit configured to execute smoothing processing of the image signal;   a compression encoding unit, provided on a subsequent stage of said smoothing unit, configured to execute compression-encoding of the image signal;   a setting unit configured to set code amounts to be respectively assigned to each picture type to said compression encoding unit;   a designation unit configured to designate a target bit rate of compression encoding of said compression encoding unit; and   a control unit configured to change an intensity of the smoothing processing by said smoothing unit and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition unit and the target bit rage designated by said designation unit,   wherein said control unit increases the intensity of the smoothing processing by said smoothing unit, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded and changes a degree of increase of the assignment ratio in accordance with the target bit rate designated by said designation unit, when the gain setting value is larger than a predetermined value.   
     
     
         33 . An image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, comprising:
 an acquisition unit configured to acquire a gain setting value for the image signal;   a compression encoding unit configured to execute compression-encoding the image signal;   a setting unit configured to set code amounts to be respectively assigned to each picture type to said compression encoding unit; and   a control unit configured to change an assignment ratio between the code amounts to be assigned to each picture types, in accordance with the gain setting value acquired by said acquisition unit,   wherein said control unit increases the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.   
     
     
         34 . A method executed by an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, the method comprising:
 an acquisition step of acquiring a gain setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of changing an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition step,   wherein said control step increases the intensity of the smoothing processing by said smoothing step, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.   
     
     
         35 . A method executed by an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, the method comprising:
 an acquisition step of acquiring a gain setting value for the image signal and a sharpness setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   an setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of controlling an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value and the sharpness setting value acquired by said acquisition step.   
     
     
         36 . A method executed by an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, the method comprising:
 an acquisition step of acquiring a gain setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step;   a designation step of designating a target bit rate of compression encoding of said compression encoding step; and   a control step of changing an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition step and the target bit rage designated by said designation step,   wherein said control step increases the intensity of the smoothing processing by said smoothing step, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded and changes a degree of increase of the assignment ratio in accordance with the target bit rate designated by said designation step, when the gain setting value is larger than a predetermined value.   
     
     
         37 . A method executed by an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, the method comprising:
 an acquisition step of acquiring a gain setting value for the image signal;   a compression encoding step of executing compression-encoding the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of changing an assignment ratio between the code amounts to be assigned to each picture types, in accordance with the gain setting value acquired by said acquisition step,   wherein said control step increases the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.   
     
     
         38 . A computer-readable storage medium on which is stored code of a computer-executable program for causing an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, to execute:
 an acquisition step of acquiring a gain setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of changing an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition step,   wherein said control step increases the intensity of the smoothing processing by said smoothing step, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.   
     
     
         39 . A computer-readable storage medium on which is stored code of a computer-executable program for causing an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, to execute:
 an acquisition step of acquiring a gain setting value for the image signal and a sharpness setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   an setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of controlling an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value and the sharpness setting value acquired by said acquisition step.   
     
     
         40 . A computer-readable storage medium on which is stored code of a computer-executable program for causing an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, to execute:
 an acquisition step of acquiring a gain setting value for the image signal;   a smoothing step of executing smoothing processing of the image signal;   a compression encoding step, provided on a subsequent stage of said smoothing step, of executing compression-encoding of the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step;   a designation step of designating a target bit rate of compression encoding of said compression encoding step; and   a control step of changing an intensity of the smoothing processing by said smoothing step and an assignment ratio between the code amounts to be assigned to each picture type, in accordance with the gain setting value acquired by said acquisition step and the target bit rage designated by said designation step,   wherein said control step increases the intensity of the smoothing processing by said smoothing step, and the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded and changes a degree of increase of the assignment ratio in accordance with the target bit rate designated by said designation step, when the gain setting value is larger than a predetermined value.   
     
     
         41 . A computer-readable storage medium on which is stored code of a computer-executable program for causing an image signal processing apparatus for classifying an image signal according to a plurality of different picture types including a picture to be intra-encoded and a picture to be encoded by inter-picture prediction and compression-encoding the image signal, to execute:
 an acquisition step of acquiring a gain setting value for the image signal;   a compression encoding step of executing compression-encoding of the image signal;   a setting step of setting code amounts to be respectively assigned to each picture type to said compression encoding step; and   a control step of changing an assignment ratio between the code amounts to be assigned to each picture types, in accordance with the gain setting value acquired by said acquisition step,   wherein said control step increases the assignment ratio of the code amount to be assigned to the picture to be encoded by inter-picture prediction with respect to the code amount to be assigned to the picture to be intra-encoded, when the gain setting value is larger than a predetermined value.