Decode progressive DC initial


FwStatus   fwiDecodeHuffman8x8_DCFirst_JPEG_1u16s_C1 ( const Fw8u * pSrcint srcLenBytesint * pSrcCurrPosFw16s * pDstFw16s * pLastDCint * pMarkerint Alconst FwiDecodeHuffmanSpec * pDcTableFwiDecodeHuffmanState * pDecHuffState );


Al   Progressive JPEG successive approximation parameter for actual point transform.
pDcTable   Pointer to the Huffman DC coefficient table.
pDecHuffState   Pointer to the FwiDecodeHuffmanState structure.
pDst   Pointer to a location in a destination buffer.
pLastDC   Pointer to the last DC coefficient, which is in the previous 8X8 block.
pMarker   Pointer to the JPEG marker position.
pSrc   Pointer to a location in a source buffer.
pSrcCurrPos   Pointer to the shift value at the current source buffer in bytes.
srcLenBytes   Source buffer length in bytes.


This function performs the first scan for progressive decoding of the DC coefficient of an 8X8 data block.

The decoding process follows CCITT Rec. T.81, Annex G.2.2.

When the function detects a JPEG marker, it stops decoding and writes the marker to the location specified by pMarker.