IDR帧属于I帧。 解码器收到IDR帧时，将所有的队列丢弃（用x264_reference_reset函 数实现——在encoder.c文件中）。这点是所有I帧共有的特性，但是收到IDR帧 时，解码器另外需要做的工作就是：把所有的PPS和SPS参数进行更新。由此可见，在编码器端，每 发一个IDR，就相应地发一个 PPS&SPS_nal_unit。

 

8148 2.0 decode demo limit

3 Limitations

These data flows have the following limitations / constraints

 These data flows are implemented for DM814x SoC.

 The software mosaic support 2 scaler instance in one SWMS. That means you can archieve

32D1@30fps performance with only one SWMS. But please don’t use VIP scaler and DEI

scaler in the same SWMS, this will cause issue. You can use VIP scaler and SC5, or SC5 with

DEI scaler.

 SD display is not supported currently

 Graphic support is not added currently

 Multiple references frames is supported but only 1 reference frame(B-frame) has been tested

extensively, hence limited Generic Decoder testing has been conducted for H264

 The numbuf should always be greater than the displaydelay and preferably the difference

between them should be five or more

 Keep the numbuf = 16 and displaydelay = 10 in the ini file, for generic streams which have

multiple reference buffers

 Limitted error stream testing has been done

 Decoder assume the first frame shall be an IDR frame (SPS/PPS + I frame)

 MPEG4-ASP is not supported

i p b 详解