func ProbeFile(filename string) (err error) {
var osfile *os.File
if osfile, err = os.Open(filename); err != nil {
return
}
var finfo os.FileInfo
if finfo, err = osfile.Stat(); err != nil {
return
}
dumper := &atom.Dumper{}
var moov *atom.Movie
lr := &io.LimitedReader{R: osfile, N: finfo.Size()}
for lr.N > 0 {
var ar *io.LimitedReader
var cc4 string
if ar, cc4, err = atom.ReadAtomHeader(lr, ""); err != nil {
log.Println("read atom failed")
return
}
if cc4 == "moov" {
if moov, err = atom.ReadMovie(ar); err != nil {
log.Println("read '%s' atom failed", cc4)
return
}
if false {
atom.WalkMovie(dumper, moov)
}
} else {
fmt.Println("atom:", cc4)
}
if _, err = atom.ReadDummy(lr, int(ar.N)); err != nil {
return
}
}
if moov == nil {
err = fmt.Errorf("'moov' atom not found")
log.Println("'moov' atom not found")
return
}
if len(moov.Tracks) > 0 {
track := moov.Tracks[0]
record := getAVCDecoderConfRecordByTrack(track)
if record != nil && len(record.SPS) > 0 {
sps := record.SPS[0]
if len(sps) > 1 {
sps = sps[1:]
log.Println(hex.Dump(sps))
var info *atom.H264SPSInfo
if info, err = atom.ParseH264SPS(sps); err != nil {
return
}
log.Println(info)
}
}
}
return
}
func TestConvert(filename string) (err error) {
var osfile *os.File
if osfile, err = os.Open(filename); err != nil {
return
}
var finfo os.FileInfo
if finfo, err = osfile.Stat(); err != nil {
return
}
log.Println("filesize", finfo.Size())
lr := &io.LimitedReader{R: osfile, N: finfo.Size()}
var outfile *os.File
if outfile, err = os.Create(filename + ".out.mp4"); err != nil {
return
}
for lr.N > 0 {
var ar *io.LimitedReader
var cc4 string
if ar, cc4, err = atom.ReadAtomHeader(lr, ""); err != nil {
return
}
if cc4 == "moov" {
curPos, _ := outfile.Seek(0, 1)
origSize := ar.N + 8
var moov *atom.Movie
if moov, err = atom.ReadMovie(ar); err != nil {
return
}
//log.Println(moov.Tracks[0].Media.Info.Data.Refer)
if err = atom.WriteMovie(outfile, moov); err != nil {
return
}
curPosAfterRead, _ := outfile.Seek(0, 1)
bytesWritten := curPosAfterRead - curPos
log.Println("regen moov", "tracks nr", len(moov.Tracks),
"origSize", origSize, "bytesWritten", bytesWritten,
)
padSize := origSize - bytesWritten - 8
aw, _ := atom.WriteAtomHeader(outfile, "free")
atom.WriteDummy(outfile, int(padSize))
aw.Close()
} else {
outcc4 := cc4
if outcc4 != "mdat" {
log.Println("omit", cc4)
outcc4 = "free"
} else {
log.Println("copy", cc4)
}
var aw *atom.Writer
if aw, err = atom.WriteAtomHeader(outfile, outcc4); err != nil {
return
}
if _, err = io.CopyN(aw, ar, ar.N); err != nil {
return
}
if err = aw.Close(); err != nil {
return
}
}
//log.Println("atom", cc4, "left", lr.N)
//atom.ReadDummy(ar, int(ar.N))
}
if err = outfile.Close(); err != nil {
return
}
return
}