Files
go2rtc/pkg/iso/iso.go
2023-01-27 12:37:02 +03:00

92 lines
1.7 KiB
Go

package iso
import (
"encoding/binary"
"math"
)
type Movie struct {
b []byte
start []int
}
func NewMovie(size int) *Movie {
return &Movie{b: make([]byte, 0, size)}
}
func (m *Movie) Bytes() []byte {
return m.b
}
func (m *Movie) StartAtom(name string) {
m.start = append(m.start, len(m.b))
m.b = append(m.b, 0, 0, 0, 0)
m.b = append(m.b, name...)
}
func (m *Movie) EndAtom() {
n := len(m.start) - 1
i := m.start[n]
size := uint32(len(m.b) - i)
binary.BigEndian.PutUint32(m.b[i:], size)
m.start = m.start[:n]
}
func (m *Movie) Write(b []byte) {
m.b = append(m.b, b...)
}
func (m *Movie) WriteBytes(b ...byte) {
m.b = append(m.b, b...)
}
func (m *Movie) WriteString(s string) {
m.b = append(m.b, s...)
}
func (m *Movie) Skip(n int) {
m.b = append(m.b, make([]byte, n)...)
}
func (m *Movie) WriteUint16(v uint16) {
m.b = append(m.b, byte(v>>8), byte(v))
}
func (m *Movie) WriteUint24(v uint32) {
m.b = append(m.b, byte(v>>16), byte(v>>8), byte(v))
}
func (m *Movie) WriteUint32(v uint32) {
m.b = append(m.b, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (m *Movie) WriteUint64(v uint64) {
m.b = append(m.b, byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (m *Movie) WriteFloat16(f float64) {
i, f := math.Modf(f)
f *= 256
m.b = append(m.b, byte(i), byte(f))
}
func (m *Movie) WriteFloat32(f float64) {
i, f := math.Modf(f)
f *= 65536
m.b = append(m.b, byte(uint16(i)>>8), byte(i), byte(uint16(f)>>8), byte(f))
}
func (m *Movie) WriteMatrix() {
m.WriteUint32(0x00010000)
m.Skip(4)
m.Skip(4)
m.Skip(4)
m.WriteUint32(0x00010000)
m.Skip(4)
m.Skip(4)
m.Skip(4)
m.WriteUint32(0x40000000)
}