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rewrite fMP4 documentation in ISO notation (#105)
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aler9 authored Jan 15, 2024
1 parent 1e7cfdf commit e9695f7
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Showing 5 changed files with 73 additions and 72 deletions.
18 changes: 9 additions & 9 deletions pkg/codecs/mpeg1audio/frame_header.go
Original file line number Diff line number Diff line change
Expand Up @@ -119,15 +119,15 @@ func (h FrameHeader) FrameLen() int {
// SampleCount returns the number of samples contained into the frame.
func (h FrameHeader) SampleCount() int {
/*
MPEG-1:
* layer 1: 384
* layer 2: 1152
* layer 3: 1152
MPEG-2:
* layer 1: 384
* layer 2: 1152
* layer 3: 576
MPEG-1:
* layer 1: 384
* layer 2: 1152
* layer 3: 1152
MPEG-2:
* layer 1: 384
* layer 2: 1152
* layer 3: 576
*/
return 1152
}
20 changes: 10 additions & 10 deletions pkg/formats/fmp4/init.go
Original file line number Diff line number Diff line change
Expand Up @@ -555,16 +555,16 @@ func (i *Init) Unmarshal(r io.ReadSeeker) error {
// Marshal encodes a fMP4 initialization file.
func (i *Init) Marshal(w io.WriteSeeker) error {
/*
- ftyp
- moov
- mvhd
- trak
- trak
- ...
- mvex
- trex
- trex
- ...
|ftyp|
|moov|
| |mvhd|
| | |trak|
| | |trak|
| | |....|
| |mvex|
| | |trex|
| | |trex|
| | |....|
*/

mw := newMP4Writer(w)
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88 changes: 44 additions & 44 deletions pkg/formats/fmp4/init_track.go
Original file line number Diff line number Diff line change
Expand Up @@ -26,50 +26,50 @@ type InitTrack struct {

func (track *InitTrack) marshal(w *mp4Writer) error {
/*
trak
- tkhd
- mdia
- mdhd
- hdlr
- minf
- vmhd (video)
- smhd (audio)
- dinf
- dref
- url
- stbl
- stsd
- av01 (AV1)
- av1C
- btrt
- vp09 (VP9)
- vpcC
- btrt
- hev1 (H265)
- hvcC
- btrt
- avc1 (H264)
- avcC
- btrt
- mp4v (MPEG-4/2/1 video, MJPEG)
- esds
- btrt
- Opus (Opus)
- dOps
- btrt
- mp4a (MPEG-4 audio)
- esds
- btrt
- mp4a (MPEG-1 audio)
- esds
- btrt
- ac-3 (AC-3)
- dac3
- btrt
- stts
- stsc
- stsz
- stco
|trak|
| |tkhd|
| |mdia|
| | |mdhd|
| | |hdlr|
| | |minf|
| | | |vmhd| (video)
| | | |smhd| (audio)
| | | |dinf|
| | | | |dref|
| | | | | |url|
| | | |stbl|
| | | | |stsd|
| | | | | |av01| (AV1)
| | | | | | |av1C|
| | | | | | |btrt|
| | | | | |vp09| (VP9)
| | | | | | |vpcC|
| | | | | | |btrt|
| | | | | |hev1| (H265)
| | | | | | |hvcC|
| | | | | | |btrt|
| | | | | |avc1| (H264)
| | | | | | |avcC|
| | | | | | |btrt|
| | | | | |mp4v| (MPEG-4/2/1 video, MJPEG)
| | | | | | |esds|
| | | | | | |btrt|
| | | | | |Opus| (Opus)
| | | | | | |dOps|
| | | | | | |btrt|
| | | | | |mp4a| (MPEG-4/1 audio)
| | | | | | |esds|
| | | | | | |btrt|
| | | | | |ac-3| (AC-3)
| | | | | | |dac3|
| | | | | | |btrt|
| | | | | |ipcm| (LPCM)
| | | | | | |pcmC|
| | | | | | |btrt|
| | | | |stts|
| | | | |stsc|
| | | | |stsz|
| | | | |stco|
*/

_, err := w.writeBoxStart(&mp4.Trak{}) // <trak>
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11 changes: 6 additions & 5 deletions pkg/formats/fmp4/part.go
Original file line number Diff line number Diff line change
Expand Up @@ -25,11 +25,12 @@ type Part struct {
// Marshal encodes a fMP4 part.
func (p *Part) Marshal(w io.WriteSeeker) error {
/*
moof
- mfhd
- traf (video)
- traf (audio)
mdat
|moof|
| |mfhd|
| | |traf|
| | |traf|
| | |....|
| |mdat|
*/

mw := newMP4Writer(w)
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8 changes: 4 additions & 4 deletions pkg/formats/fmp4/part_track.go
Original file line number Diff line number Diff line change
Expand Up @@ -13,10 +13,10 @@ type PartTrack struct {

func (pt *PartTrack) marshal(w *mp4Writer) (*mp4.Trun, int, error) {
/*
traf
- tfhd
- tfdt
- trun
|traf|
| |tfhd|
| |tfdt|
| |trun|
*/

_, err := w.writeBoxStart(&mp4.Traf{}) // <traf>
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