Encode progressive DC initial
| FwStatus | fwiEncodeHuffman8x8_DCFirst_JPEG_16s1u_C1 | ( | const Fw16s * pSrc, Fw8u * pDst, int dstLenBytes, int * pDstCurrPos, Fw16s * pLastDC, int Al, const FwiEncodeHuffmanSpec * pDcTable, FwiEncodeHuffmanState * pEncHuffState, int bFlushState ); |
| Al | Progressive JPEG successive approximation parameter for actual point transform. | |
| bFlushState | Indicates the last 8X8 block in a scan. | |
| dstLenBytes | Destination buffer length in bytes. | |
| pDcTable | Pointer to the Huffman DC coefficient table. | |
| pDst | Pointer to a location in a destination buffer. | |
| pDstCurrPos | Pointer to the shift value at the current destination buffer in bytes. | |
| pEncHuffState | Pointer to the FwiEncodeHuffmanState structure. | |
| pLastDC | Pointer to the last DC coefficient, which is in the previous 8X8 block. | |
| pSrc | Pointer to a location in a source buffer. |
This function performs the first scan for progressive encoding of the DC coefficient of an 8X8 data block.
The encoding process follows CCITT Rec. T.81, Annex G.1.2. The function writes only full bytes to the output buffer.
Incomplete bits from data blocks in a stream are accumulated in the Huffman encode state structure.
To place all the accumulated bits in the buffer, set the bFlashState bit to 1 before processing the last 8X8 block in the stream, or restart the encoded interval.