Specifications

4
4CIF is the highest resolution, providing the maximum level of detail and resulting in the crispest,
clearest images. For NTSC and PAL images that come from an interlaced source, the QCIF, CIF, and
2CIF resolutions will use only one of the two fields from a typical video signal, avoiding potential
artifacts that result from interlacing. See the table below for the number of columns and lines for each
resolution.
Resolution Number of
Columns
Number of Lines
NTSC/PAL NTSC PAL
QCIF 176 128 144
CIF 352 240 288
2CIFH 704 240 288
4CIF 704 480 576
All Lines (HD1) 352 480 576
2/3 D1 480 480 576
VGA 640 480 576
Quantization (Minimum and Maximum Quantizer)
Quantization is the process of approximating a continuous range of values. Quantization plays a major
role in data compression, reducing the amount of data needed to represent a signal. Together, the
Minimum and Maximum Quantizers establish the “quality” boundaries of a video codec rate controller.
A low quantizer setting will generate high-quality video, resulting in bigger files. A high quantizer
setting will generate low-quality video, resulting in smaller files. Quantizer values range from 2 to 31.
The Minimum Quantizer establishes the high-quality boundary, while the Maximum Quantizer
establishes the low-quality boundary:
• A minimum of 2 is recommended for optimum quality. You can increase the minimum if you
want to reduce the required bandwidth and storage when there is no motion. Normally, the
Minimum Quantizer should not be set at more than 6.
• A maximum of 6 is recommended if high-quality video is a priority. The maximum should be
30 if maintaining frame rate is important.
• If you want consistent quality, use the same settings for both the Minimum and Maximum
Quantizers.
NOTE: In 95% of the cases, when the encoder does not sustain its Target Frame Rate, it is because
the Maximum Quantizer is not set high enough. Set it higher or, if you do not mind exceeding the
Target Bit Rate, set the rate control mode to CFR.