hpm_jpeg_sos_info Struct Reference

Data Fields
uint16_t	ls
uint8_t	ns
struct {
uint8_t   cs
uint8_t   ta: 4
uint8_t   td: 4
}	component [4]
uint8_t	ss
uint8_t	se
uint8_t	al: 4
uint8_t	ah: 4

Field Documentation

ah

uint8_t hpm_jpeg_sos_info::ah

Ah: Successive approximation bit position high. This parameter shall be set to 0 for the first scan of each band of coefficients. In the lossless mode of operations this parameter has no meaning. It shall be set to 0

al

uint8_t hpm_jpeg_sos_info::al

Al: Successive approximation bit position low or point transform. This parameter shall be set to zero for the sequential DCT processes

struct { ... } hpm_jpeg_sos_info::component[4]

Component-specification parameters

cs

uint8_t hpm_jpeg_sos_info::cs

Csj: Scan component selector – Selects which of the Nf image components specified in the frame parameters shall be the jth component in the scan. 1: Y, 2: Cb, 3: Cr

ls

uint16_t hpm_jpeg_sos_info::ls

Ls: Scan header length

ns

uint8_t hpm_jpeg_sos_info::ns

Ns: Number of image components in scan – Specifies the number of source image components in the scan

se

uint8_t hpm_jpeg_sos_info::se

Se: End of spectral selection. This parameter shall be set to 63 for the sequential DCT processes

ss

uint8_t hpm_jpeg_sos_info::ss

Ss: Start of spectral or predictor selection. This parameter shall be set to 0 for the sequential DCT processes

ta

uint8_t hpm_jpeg_sos_info::ta

Taj: AC entropy coding table destination selector – Specifies one of four possible AC entropy coding table destinations from which the entropy table needed for decoding of the AC coefficients of component Csj is retrieved

td

uint8_t hpm_jpeg_sos_info::td

Tdj: DC entropy coding table destination selector – Specifies one of four possible DC entropy coding table destinations from which the entropy table needed for decoding of the DC coefficients of component Csj is retrieved

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The documentation for this struct was generated from the following file:

• components/jpeg/hpm_jpeg.c