mp4文件数据格式解析

unsigned int(32)[3]    32*3bit

string[32]  32*8bit

class VisualSampleEntry(codingname) extends SampleEntry (codingname){
unsigned int(16) pre_defined = 0;
const unsigned int(16) reserved = 0;
unsigned int(32)[3] pre_defined = 0;
unsigned int(16) width;
unsigned int(16) height;
template unsigned int(32) horizresolution = 0x00480000; // 72 dpi
template unsigned int(32) vertresolution = 0x00480000; // 72 dpi
const unsigned int(32) reserved = 0;
template unsigned int(16) frame_count = 1;
string[32] compressorname;
template unsigned int(16) depth = 0x0018;
int(16) pre_defined = -1;
// other boxes from derived specifications
CleanApertureBox clap; // optional
PixelAspectRatioBox pasp; // optional
}