Texas Instruments DM6467, Руководство пользователя

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Introduction
1-4
Figure 1-1 depicts the working of the H.264 Encoder algorithm.
Figure 1-1. Working of H.264 Video Encoder
In H.264 Encoder, the operations are performed on a set of specific N
macro blocks. The value of N at the most can be 2. The operations such as
Motion Compensation, Transform and Quantization, Run Length Encoding
and Inverse Quantization, and Inverse Transform Blocks are called once,
for all the inter macro blocks in the set of N.
In motion estimation, the encoder searches for the best match in the
available reference frame(s). After quantization, contents of some blocks
become zero.
The H.264 Encoder defines in-loop filtering to avoid blocks across the 4x4
block boundaries. It is the second most computational task of H.264
encoding process after motion estimation. In-loop filtering is applied on all
4x4 edges as a post-process and the operations depend on the edge
strength of the particular edge.
The H.264 Encoder applies entropy-coding methods to use context-based
adaptivity, which improves the coding performance. All the macro blocks,
which belong to a slice, must be encoded in a raster scan order. Baseline
profile uses the Context Adaptive Variable Length Coding (CAVLC).
CAVLC is the stage where transformed and quantized co-efficients are
entropy coded using context adaptive table switching across different
symbols. The syntax defined by the H.264 Encoder stores the information
at 4x4 block level.
From this point onwards, all references to H.264 Encoder means H.264
1080p@30 Baseline Profile Encoder only.