Hsi Yang Wu

US Patent:

7692682, Apr 6, 2010

Filed:

Apr 28, 2005

Appl. No.:

11/118615

Inventors:

Thomas Pun - San Jose CA, US
Hsi Jung Wu - Sunnyvale CA, US
Hyeonkuk Jeong - San Jose CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/15

US Classification:

348 1408

Abstract:

Some embodiments provide an architecture for establishing multi-participant video conferences. This architecture has a central distributor that receives video images from two or more participants. From the received images, the central distributor generates composite images that the central distributor transmits back to the participants. Each composite image includes a set of sub images, where each sub image belongs to one participant. In some embodiments, the central distributor saves network bandwidth by removing each particular participant's image from the composite image that the central distributor sends to the particular participant. In some embodiments, images received from each participant are arranged in the composite in a non-interleaved manner. For instance, in some embodiments, the composite image includes at most one sub-image for each participant, and no two sub-images are interleaved.

US Patent:

8005139, Aug 23, 2011

Filed:

Apr 28, 2005

Appl. No.:

11/118604

Inventors:

Hsi Jung Wu - Sunnyvale CA, US
Thomas Pun - San Jose CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/12

US Classification:

37524003, 37524002

Abstract:

Some embodiments of the invention encode a sequence of video images based on “visual masking” attributes of the video images and/or portions of the video images. Visual masking of an image or a portion of the image is an indication of how much coding artifacts can be tolerated in the image or image portion. To express the visual masking attribute of an image or an image portion, some embodiments compute a visual masking strength that quantifies the brightness energy of the image or the image portion. In some embodiments, the brightness energy is measured as a function of the average luma or pixel energy of the image or image portion.

US Patent:

8111752, Feb 7, 2012

Filed:

Apr 28, 2005

Appl. No.:

11/119428

Inventors:

Roger Kumar - San Francisco CA, US
Thomas Pun - San Jose CA, US
Hsi Jung Wu - Sunnyvale CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/12

US Classification:

37524016

Abstract:

A method for encoding a first set of pixels in a first image in a sequence of images is described. From a set of encoding modes, the method selects a first mode for encoding the first set of pixels. The method then determines whether encoding the first set of pixels in the first mode satisfies a set of quality criteria. The method foregoes encoding the first set of pixels in a second mode from the set of encoding modes, when the first mode encoding satisfies the set of quality criteria. The method also provides a video encoding method that examines several different methods for encoding a set of pixels in a first image. From a list of possible encoding modes, the method eliminates a set of encoding modes that are not likely to provide a suitable encoding solution. The method then examines different encoding solutions based on the remaining encoding modes in the list.

US Patent:

8269816, Sep 18, 2012

Filed:

Feb 8, 2010

Appl. No.:

12/702287

Inventors:

Thomas Pun - San Jose CA, US
Hsi Jung Wu - Sunnyvale CA, US
Hyeonkuk Jeong - San Jose CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/14

US Classification:

348 141, 348 1413, 348 1415, 37524002, 37524009, 37524013, 37524015, 37524017, 709202

Abstract:

Some embodiments provide an architecture for establishing multi-participant video conferences. This architecture has a central distributor that receives video images from two or more participants. From the received images, the central distributor generates composite images that the central distributor transmits back to the participants. Each composite image includes a set of sub images, where each sub image belongs to one participant. In some embodiments, the central distributor saves network bandwidth by removing each particular participant's image from the composite image that the central distributor sends to the particular participant. In some embodiments, images received from each participant are arranged in the composite in a non-interleaved manner. For instance, in some embodiments, the composite image includes at most one sub-image for each participant, and no two sub-images are interleaved.

US Patent:

8406293, Mar 26, 2013

Filed:

Apr 28, 2005

Appl. No.:

11/118616

Inventors:

Xin Tong - Mountain View CA, US
Hsi Jung Wu - Sunnyvale CA, US
Thomas Pun - San Jose CA, US
Adriana Dumitras - Sunnyvale CA, US
Barin Geoffry Haskell - Mountain View CA, US
Jim Normile - Los Altos CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/12

US Classification:

37524003

Abstract:

A novel multi-pass encoding method that encodes several images (e. g. , several frames of a video sequence) is described. The method iteratively performs an encoding operation that encodes these images. The encoding operation is based on a nominal quantization parameter, which the method uses to compute quantization parameter for the images. During several different iterations of the encoding operation, the method uses several different nominal quantization parameters. The method stops its iterations when it reaches a terminating criterion (e. g. , it identifies an acceptable encoding of the images).

US Patent:

8520053, Aug 27, 2013

Filed:

Jul 27, 2012

Appl. No.:

13/560962

Inventors:

Thomas Pun - San Jose CA, US
Hsi Jung Wu - Sunnyvale CA, US
Hyeonkuk Jeong - San Jose CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/14

US Classification:

348 141, 348 1409, 348 1415, 370265, 370269, 37920201, 709204

Abstract:

Some embodiments provide an architecture for establishing multi-participant video conferences. This architecture has a central distributor that receives video images from two or more participants. From the received images, the central distributor generates composite images that the central distributor transmits back to the participants. Each composite image includes a set of sub images, where each sub image belongs to one participant. In some embodiments, the central distributor saves network bandwidth by removing each particular participant's image from the composite image that the central distributor sends to the particular participant. In some embodiments, images received from each participant are arranged in the composite in a non-interleaved manner. For instance, in some embodiments, the composite image includes at most one sub-image for each participant, and no two sub-images are interleaved.

US Patent:

8594190, Nov 26, 2013

Filed:

Jul 8, 2011

Appl. No.:

13/179476

Inventors:

Hsi Jung Wu - Sunnyvale CA, US
Thomas Pun - San Jose CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/12

US Classification:

37524003, 37524002

Abstract:

Some embodiments of the invention encode a sequence of video images based on “visual masking” attributes of the video images and/or portions of the video images. Visual masking of an image or a portion of the image is an indication of how much coding artifacts can be tolerated in the image or image portion. To express the visual masking attribute of an image or an image portion, some embodiments compute a visual masking strength that quantifies the brightness energy of the image or the image portion. In some embodiments, the brightness energy is measured as a function of the average luma or pixel energy of the image or image portion.

US Patent:

8208536, Jun 26, 2012

Filed:

Apr 28, 2005

Appl. No.:

11/118618

Inventors:

Thomas Pun - San Jose CA, US
Hsi Jung Wu - Sunnyvale CA, US
Adriana Dumitras - Sunnyvale CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H04N 7/12

US Classification:

37524003

Abstract:

A method is used for specifying a bit allocation for encoding a set of images in a sequence of video images. The method computes a masking value for one or more images. The method computes a bit allocation for a current image based on the computed masking value of one or more images. The method further ascertains a total number of bits used for images that have been already encoded before computing the bit allocation. The computed bit allocation for the current image is also based on the total number of bits used. The method specifies a bit allocation for the current image by specifying a quantization parameter (QP) value for the current image. The method then adjusts the specified QP value based on a categorization of the current image.