3.3.8.1 ClearCodec Compression

The ClearCodec Codec is used to encode bitmaps sent in the RDPGFX_WIRE_TO_SURFACE_PDU_1 (section 2.2.2.1) message. The encoded bitmap data MUST be transported in the bitmapData field of the RDPGFX_WIRE_TO_SURFACE_PDU_1 message, and the codecId field MUST be set to RDPGFX_CODECID_CLEARCODEC (0x0008).

The ClearCodec bitmap stream is described in section 2.2.4.1 and is composed of a maximum of three layers. Each layer is optional and is encoded using different techniques.

• The residual layer (section 2.2.4.1.1.1)

• The bands layer (section 2.2.4.1.1.2)

• The subcodec layer (section 2.2.4.1.1.3)