Hi~. I'm testing ipp7.0 sample code for jpeg decoding.
An interest thing is there is no defintion about YUV420 format(not pixel but planar).
The supported sampling formats are
JS_444, JS_422, JS_244, JS_411, JS_OTHER.
In addition, I think the function, JERRCODE CJPEGDecoder::DetectSampling(void) function in jpegdec.cpp file is used for acquring sampling format.
By the way, inside the function,
case 3:
if(m_ccomp[0].m_hsampling == 1 && m_ccomp[0].m_vsampling == 1 &&
m_ccomp[1].m_hsampling == 1 && m_ccomp[1].m_vsampling == 1 &&
m_ccomp[2].m_hsampling == 1 && m_ccomp[2].m_vsampling == 1)
{
m_jpeg_sampling = JS_444;
}
else if(m_ccomp[0].m_hsampling == 2 && m_ccomp[0].m_vsampling == 1 &&
m_ccomp[1].m_hsampling == 1 && m_ccomp[1].m_vsampling == 1 &&
m_ccomp[2].m_hsampling == 1 && m_ccomp[2].m_vsampling == 1)
{
m_jpeg_sampling = JS_422; <=== Is this correct? YUV420 is also the same hsampling and vsampling value if the function search the sampling like this. Isn't it?
}
If I am wrong, please forgive my ignorance. Anyway I would like to know how to decode YUV420 encoded jpeg image without using additional converting such as YUV422toYUV420....with ipp.
Many thanks ahead.
