Single-instruction multiple-data (SIMD)-based algorithms for processing video data

A method of processing a discrete cosine transform (DCT) block of coefficients, the method comprising the steps of:

• (a) receiving a DCT block of coefficients;
• (b) linearizing the DCT block of coefficients into a one dimensional array of sequentially arranged DCT coefficients;
• (c) concurrently storing a portion of the one dimensional array of DCT coefficients in a first register, the portion including at least two sequentially arranged DCT coefficients;
• (d) storing weighting elements in a second register, each of the weighting elements corresponding to a respective DCT coefficient stored in the first register;
• and
• (e) concurrently multiplying each of the weighting elements stored in the second register with the respective DCT coefficient stored in the first register.

A method of obtaining a run length value of a DCT block of coefficients in a video encoder/decoder, the method comprising the steps of:

• (a) receiving a DCT block of coefficients;
• (b) linearizing the DCT block of coefficients into a one dimensional array of sequentially arranged DCT coefficients;
• (c) storing a portion of the one dimensional array of DCT coefficients in a register, the portion including at least two sequentially arranged DCT coefficients;
• (d) concurrently comparing the DCT coefficients stored in the register with a set of zero values stored in another register;
• and
• (e) determining a run length value of the DCT coefficients responsive to the comparison of step (d).

A method of obtaining a class number of a DCT block of coefficients in a video encoder/decoder, the method comprising the steps of:

• (a) receiving a DCT block of coefficients;
• (b) linearizing the DCT block of coefficients into a one dimensional array of sequentially arranged DCT coefficients;
• (c) storing a portion of the one dimensional array of DCT coefficients in a register, the portion including at least two sequentially arranged DCT coefficients;
• (d) weighting each of the DCT coefficients stored in the register;
• (e) obtaining an absolute value of each of the weighted DCT coefficients;
• (f) comparing the absolute value of each of the weighted DCT coefficients with a predetermined value;
• and
• (g) classifying the DCT block with a first predetermined class number, if any DCT coefficient compared in step (f) is greater than the predetermined value.

A method of dequantizing a DCT block of coefficients in a video decoder, the method comprising the steps of:

• (a) storing a portion of the DCT block of coefficients in a first register, the portion including at least two DCT coefficients;
• (b) storing weighting values in a second register;
• and
• (c) multiplying each DCT coefficient stored in the first register with a corresponding weighted value in the second register to obtain the dequantized DCT block of coefficients.