package/gortsplib
1
0
Fork 0
mirror of https://github.com/aler9/gortsplib synced 2025-10-06 23:52:46 +08:00
Code Issues Packages Projects Releases Wiki Activity

h264: fix Annex-B decoding

Browse Source 
Some Annex-B streams use both [0 0 1] and [0 0 0 1] as delimiters.
These streams are now parsed correctly.
This commit is contained in:
aler9
2022-10-08 20:06:42 +02:00
parent 92cc1b5ee9
commit b3c70f56f7
2 changed files with 63 additions and 44 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
pkg/h264/annexb.go
View File

@@ -1,20 +1,19 @@
package h264
import (
"bytes"
"fmt"
)
// AnnexBUnmarshal decodes NALUs from the Annex-B stream format.
func AnnexBUnmarshal(byts []byte) ([][]byte, error) {
bl := len(byts)
zeroCount := 0
initZeroCount := 0
outer:
for i := 0; i < bl; i++ {
switch byts[i] {
case 0:
zeroCount++
initZeroCount++
case 1:
break outer
@@ -23,35 +22,46 @@ outer:
return nil, fmt.Errorf("unexpected byte: %d", byts[i])
}
}
if zeroCount != 2 && zeroCount != 3 {
if initZeroCount != 2 && initZeroCount != 3 {
return nil, fmt.Errorf("initial delimiter not found")
}
start := zeroCount + 1
start := initZeroCount + 1
zeroCount := 0
n := 0
var n int
if zeroCount == 2 {
n = bytes.Count(byts[start:], []byte{0x00, 0x00, 0x01})
} else {
n = bytes.Count(byts[start:], []byte{0x00, 0x00, 0x00, 0x01})
for i := start; i < bl; i++ {
switch byts[i] {
case 0:
zeroCount++
case 1:
if zeroCount == 2 || zeroCount == 3 {
n++
}
zeroCount = 0
default:
zeroCount = 0
}
}
ret := make([][]byte, n+1)
pos := 0
curZeroCount := 0
start = initZeroCount + 1
zeroCount = 0
delimStart := 0
for i := start; i < bl; i++ {
switch byts[i] {
case 0:
if curZeroCount == 0 {
if zeroCount == 0 {
delimStart = i
}
curZeroCount++
zeroCount++
case 1:
if curZeroCount == zeroCount {
if zeroCount == 2 || zeroCount == 3 {
if (delimStart - start) > MaxNALUSize {
return nil, fmt.Errorf("NALU size (%d) is too big (maximum is %d)", delimStart-start, MaxNALUSize)
}
@@ -65,10 +75,10 @@ outer:
pos++
start = i + 1
}
curZeroCount = 0
zeroCount = 0
default:
curZeroCount = 0
zeroCount = 0
}
}

63
pkg/h264/annexb_test.go
View File

@@ -13,23 +13,15 @@ var casesAnnexB = []struct {
dec [][]byte
}{
{
"2 zeros, single",
[]byte{0x00, 0x00, 0x01, 0xaa, 0xbb},
[]byte{0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb},
[][]byte{
{0xaa, 0xbb},
},
},
{
"2 zeros, multiple",
"2 zeros",
[]byte{
0x00, 0x00, 0x01, 0xaa, 0xbb, 0x00, 0x00, 0x01,
0xcc, 0xdd, 0x00, 0x00, 0x01, 0xee, 0xff,
},
[]byte{
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb, 0x00, 0x00,
0x00, 0x01, 0xcc, 0xdd, 0x00, 0x00, 0x00, 0x01,
0xee, 0xff,
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb,
0x00, 0x00, 0x00, 0x01, 0xcc, 0xdd,
0x00, 0x00, 0x00, 0x01, 0xee, 0xff,
},
[][]byte{
{0xaa, 0xbb},
@@ -38,24 +30,16 @@ var casesAnnexB = []struct {
},
},
{
"3 zeros, single",
[]byte{0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb},
[]byte{0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb},
[][]byte{
{0xaa, 0xbb},
},
},
{
"3 zeros, multiple",
"3 zeros",
[]byte{
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb, 0x00, 0x00,
0x00, 0x01, 0xcc, 0xdd, 0x00, 0x00, 0x00, 0x01,
0xee, 0xff,
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb,
0x00, 0x00, 0x00, 0x01, 0xcc, 0xdd,
0x00, 0x00, 0x00, 0x01, 0xee, 0xff,
},
[]byte{
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb, 0x00, 0x00,
0x00, 0x01, 0xcc, 0xdd, 0x00, 0x00, 0x00, 0x01,
0xee, 0xff,
0x00, 0x00, 0x00, 0x01, 0xaa, 0xbb,
0x00, 0x00, 0x00, 0x01, 0xcc, 0xdd,
0x00, 0x00, 0x00, 0x01, 0xee, 0xff,
},
[][]byte{
{0xaa, 0xbb},
@@ -63,6 +47,31 @@ var casesAnnexB = []struct {
{0xee, 0xff},
},
},
{
// used by Apple inside HLS test streams
"2 or 3 zeros",
[]byte{
0, 0, 0, 1, 9, 240,
0, 0, 0, 1, 39, 66, 224, 21, 169, 24, 60, 23, 252, 184, 3, 80, 96, 16, 107, 108, 43, 94, 247, 192, 64,
0, 0, 0, 1, 40, 222, 9, 200,
0, 0, 1, 6, 0, 7, 131, 236, 119, 0, 0, 0, 0, 1, 3, 0, 64, 128,
0, 0, 1, 6, 5, 17, 3, 135, 244, 78, 205, 10, 75, 220, 161, 148, 58, 195, 212, 155, 23, 31, 0, 128,
},
[]byte{
0, 0, 0, 1, 9, 240,
0, 0, 0, 1, 39, 66, 224, 21, 169, 24, 60, 23, 252, 184, 3, 80, 96, 16, 107, 108, 43, 94, 247, 192, 64,
0, 0, 0, 1, 40, 222, 9, 200,
0, 0, 0, 1, 6, 0, 7, 131, 236, 119, 0, 0, 0, 0, 1, 3, 0, 64, 128,
0, 0, 0, 1, 6, 5, 17, 3, 135, 244, 78, 205, 10, 75, 220, 161, 148, 58, 195, 212, 155, 23, 31, 0, 128,
},
[][]byte{
{9, 240},
{39, 66, 224, 21, 169, 24, 60, 23, 252, 184, 3, 80, 96, 16, 107, 108, 43, 94, 247, 192, 64},
{40, 222, 9, 200},
{6, 0, 7, 131, 236, 119, 0, 0, 0, 0, 1, 3, 0, 64, 128},
{6, 5, 17, 3, 135, 244, 78, 205, 10, 75, 220, 161, 148, 58, 195, 212, 155, 23, 31, 0, 128},
},
},
}
func TestAnnexBUnmarshal(t *testing.T) {