公开(公告)号：US20210352282A1

公开(公告)日：2021-11-11

申请号：US17385030

申请日：2021-07-26

Applicant: ATI Technologies ULC

Inventor： Feng Pan ,  Wei Gao ,  Yang Liu ,  Crystal Yeong-Pian Sau ,  Haibo Liu ,  Edward A. Harold ,  Ying Luo ,  Ihab Amer ,  Gabor Sines

IPC: H04N19/115 ,  H04N19/176 ,  H04N19/182 ,  H04N19/186

Abstract: Systems, apparatuses, and methods for calculating multi-pass histograms for palette table derivation are disclosed. An encoder calculates a first histogram for a first portion of most significant bits (MSBs) of pixel component values of a block of an image or video frame. Then, the encoder selects a given number of the highest pixel count bins from the first histogram. The encoder then increases the granularity of these selected highest pixel count bins by evaluating one or more additional bits from the pixel component values. A second histogram is calculated for the concatenation of the original first portion MSBs from the highest pixel count bins and the one or more additional bits, and the highest pixel count bins are selected from the second histogram. A palette table is derived based on these highest pixel count bins selected from the second histogram, and the block is encoded using the palette table.

公开(公告)号：US20210097327A1

公开(公告)日：2021-04-01

申请号：US16588810

申请日：2019-09-30

Applicant: ATI Technologies ULC

Inventor： Feng Pan ,  Wei Gao ,  Yang Liu ,  Crystal Yeong-Pian Sau ,  Haibo Liu ,  Edward A. Harold ,  Ying Luo ,  Ihab Amer ,  Gabor Sines

IPC: G06K9/46 ,  G06T5/40 ,  G06K9/62 ,  H04N19/186 ,  H04N19/423

Abstract: Systems, apparatuses, and methods for performing parallel histogram calculation with application to palette table derivation are disclosed. An encoder calculates a first histogram for a first portion of pixel component value bits of a block of pixels. Then, the encoder selects a first number of the highest pixel count bins from the first histogram. Also, the encoder calculates a second histogram for a second portion of pixel component value bits of the block. The encoder selects a second number of the highest pixel count bins from the second histogram. A third histogram is calculated from the concatenation of bits assigned to the first and second number of bins, and the highest pixel count bins are selected from the third histogram. A palette table is derived based on these highest pixel count bins selected from the third histogram, and the block of pixels is encoded using the palette table.