mirror of
https://github.com/aler9/gortsplib
synced 2025-10-05 07:06:58 +08:00
729 lines
16 KiB
Go
729 lines
16 KiB
Go
package h264
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
"github.com/bluenviron/gortsplib/v3/pkg/bits"
|
|
)
|
|
|
|
const (
|
|
maxRefFrames = 255
|
|
)
|
|
|
|
func readScalingList(buf []byte, pos *int, size int) ([]int32, bool, error) {
|
|
lastScale := int32(8)
|
|
nextScale := int32(8)
|
|
scalingList := make([]int32, size)
|
|
var useDefaultScalingMatrixFlag bool
|
|
|
|
for j := 0; j < size; j++ {
|
|
if nextScale != 0 {
|
|
deltaScale, err := bits.ReadGolombSigned(buf, pos)
|
|
if err != nil {
|
|
return nil, false, err
|
|
}
|
|
|
|
nextScale = (lastScale + deltaScale + 256) % 256
|
|
useDefaultScalingMatrixFlag = (j == 0 && nextScale == 0)
|
|
}
|
|
|
|
if nextScale == 0 {
|
|
scalingList[j] = lastScale
|
|
} else {
|
|
scalingList[j] = nextScale
|
|
}
|
|
|
|
lastScale = scalingList[j]
|
|
}
|
|
|
|
return scalingList, useDefaultScalingMatrixFlag, nil
|
|
}
|
|
|
|
// SPS_HRD is a hypotetical reference decoder.
|
|
type SPS_HRD struct { //nolint:revive
|
|
CpbCntMinus1 uint32
|
|
BitRateScale uint8
|
|
CpbSizeScale uint8
|
|
BitRateValueMinus1 []uint32
|
|
CpbSizeValueMinus1 []uint32
|
|
CbrFlag []bool
|
|
InitialCpbRemovalDelayLengthMinus1 uint8
|
|
CpbRemovalDelayLengthMinus1 uint8
|
|
DpbOutputDelayLengthMinus1 uint8
|
|
TimeOffsetLength uint8
|
|
}
|
|
|
|
func (h *SPS_HRD) unmarshal(buf []byte, pos *int) error {
|
|
var err error
|
|
h.CpbCntMinus1, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
err = bits.HasSpace(buf, *pos, 8)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
h.BitRateScale = uint8(bits.ReadBitsUnsafe(buf, pos, 4))
|
|
h.CpbSizeScale = uint8(bits.ReadBitsUnsafe(buf, pos, 4))
|
|
|
|
for i := uint32(0); i <= h.CpbCntMinus1; i++ {
|
|
v, err := bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
h.BitRateValueMinus1 = append(h.BitRateValueMinus1, v)
|
|
|
|
v, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
h.CpbSizeValueMinus1 = append(h.CpbSizeValueMinus1, v)
|
|
|
|
vb, err := bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
h.CbrFlag = append(h.CbrFlag, vb)
|
|
}
|
|
|
|
err = bits.HasSpace(buf, *pos, 5+5+5+5)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
h.InitialCpbRemovalDelayLengthMinus1 = uint8(bits.ReadBitsUnsafe(buf, pos, 5))
|
|
h.CpbRemovalDelayLengthMinus1 = uint8(bits.ReadBitsUnsafe(buf, pos, 5))
|
|
h.DpbOutputDelayLengthMinus1 = uint8(bits.ReadBitsUnsafe(buf, pos, 5))
|
|
h.TimeOffsetLength = uint8(bits.ReadBitsUnsafe(buf, pos, 5))
|
|
|
|
return nil
|
|
}
|
|
|
|
// SPS_TimingInfo is a timing info.
|
|
type SPS_TimingInfo struct { //nolint:revive
|
|
NumUnitsInTick uint32
|
|
TimeScale uint32
|
|
FixedFrameRateFlag bool
|
|
}
|
|
|
|
func (t *SPS_TimingInfo) unmarshal(buf []byte, pos *int) error {
|
|
err := bits.HasSpace(buf, *pos, 32+32+1)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
t.NumUnitsInTick = uint32(bits.ReadBitsUnsafe(buf, pos, 32))
|
|
t.TimeScale = uint32(bits.ReadBitsUnsafe(buf, pos, 32))
|
|
t.FixedFrameRateFlag = bits.ReadFlagUnsafe(buf, pos)
|
|
|
|
return nil
|
|
}
|
|
|
|
// SPS_BitstreamRestriction are bitstream restriction infos.
|
|
type SPS_BitstreamRestriction struct { //nolint:revive
|
|
MotionVectorsOverPicBoundariesFlag bool
|
|
MaxBytesPerPicDenom uint32
|
|
MaxBitsPerMbDenom uint32
|
|
Log2MaxMvLengthHorizontal uint32
|
|
Log2MaxMvLengthVertical uint32
|
|
MaxNumReorderFrames uint32
|
|
MaxDecFrameBuffering uint32
|
|
}
|
|
|
|
func (r *SPS_BitstreamRestriction) unmarshal(buf []byte, pos *int) error {
|
|
var err error
|
|
r.MotionVectorsOverPicBoundariesFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.MaxBytesPerPicDenom, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.MaxBitsPerMbDenom, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.Log2MaxMvLengthHorizontal, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.Log2MaxMvLengthVertical, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.MaxNumReorderFrames, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
r.MaxDecFrameBuffering, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// SPS_VUI is a video usability information.
|
|
type SPS_VUI struct { //nolint:revive
|
|
AspectRatioInfoPresentFlag bool
|
|
|
|
// AspectRatioInfoPresentFlag == true
|
|
AspectRatioIdc uint8
|
|
SarWidth uint16
|
|
SarHeight uint16
|
|
|
|
OverscanInfoPresentFlag bool
|
|
|
|
// OverscanInfoPresentFlag == true
|
|
OverscanAppropriateFlag bool
|
|
VideoSignalTypePresentFlag bool
|
|
|
|
// VideoSignalTypePresentFlag == true
|
|
VideoFormat uint8
|
|
VideoFullRangeFlag bool
|
|
ColourDescriptionPresentFlag bool
|
|
|
|
// ColourDescriptionPresentFlag == true
|
|
ColourPrimaries uint8
|
|
TransferCharacteristics uint8
|
|
MatrixCoefficients uint8
|
|
|
|
ChromaLocInfoPresentFlag bool
|
|
|
|
// ChromaLocInfoPresentFlag == true
|
|
ChromaSampleLocTypeTopField uint32
|
|
ChromaSampleLocTypeBottomField uint32
|
|
|
|
TimingInfo *SPS_TimingInfo
|
|
NalHRD *SPS_HRD
|
|
VclHRD *SPS_HRD
|
|
|
|
LowDelayHrdFlag bool
|
|
PicStructPresentFlag bool
|
|
BitstreamRestriction *SPS_BitstreamRestriction
|
|
}
|
|
|
|
func (v *SPS_VUI) unmarshal(buf []byte, pos *int) error {
|
|
var err error
|
|
v.AspectRatioInfoPresentFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if v.AspectRatioInfoPresentFlag {
|
|
tmp, err := bits.ReadBits(buf, pos, 8)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
v.AspectRatioIdc = uint8(tmp)
|
|
|
|
if v.AspectRatioIdc == 255 { // Extended_SAR
|
|
err := bits.HasSpace(buf, *pos, 32)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
v.SarWidth = uint16(bits.ReadBitsUnsafe(buf, pos, 16))
|
|
v.SarHeight = uint16(bits.ReadBitsUnsafe(buf, pos, 16))
|
|
}
|
|
}
|
|
|
|
v.OverscanInfoPresentFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if v.OverscanInfoPresentFlag {
|
|
v.OverscanAppropriateFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
v.VideoSignalTypePresentFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if v.VideoSignalTypePresentFlag {
|
|
err := bits.HasSpace(buf, *pos, 5)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
v.VideoFormat = uint8(bits.ReadBitsUnsafe(buf, pos, 3))
|
|
v.VideoFullRangeFlag = bits.ReadFlagUnsafe(buf, pos)
|
|
v.ColourDescriptionPresentFlag = bits.ReadFlagUnsafe(buf, pos)
|
|
|
|
if v.ColourDescriptionPresentFlag {
|
|
err := bits.HasSpace(buf, *pos, 24)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
v.ColourPrimaries = uint8(bits.ReadBitsUnsafe(buf, pos, 8))
|
|
v.TransferCharacteristics = uint8(bits.ReadBitsUnsafe(buf, pos, 8))
|
|
v.MatrixCoefficients = uint8(bits.ReadBitsUnsafe(buf, pos, 8))
|
|
}
|
|
}
|
|
|
|
v.ChromaLocInfoPresentFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if v.ChromaLocInfoPresentFlag {
|
|
v.ChromaSampleLocTypeTopField, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
v.ChromaSampleLocTypeBottomField, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
timingInfoPresentFlag, err := bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if timingInfoPresentFlag {
|
|
v.TimingInfo = &SPS_TimingInfo{}
|
|
err := v.TimingInfo.unmarshal(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
nalHrdParametersPresentFlag, err := bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if nalHrdParametersPresentFlag {
|
|
v.NalHRD = &SPS_HRD{}
|
|
err := v.NalHRD.unmarshal(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
vclHrdParametersPresentFlag, err := bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if vclHrdParametersPresentFlag {
|
|
v.VclHRD = &SPS_HRD{}
|
|
err := v.VclHRD.unmarshal(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if nalHrdParametersPresentFlag || vclHrdParametersPresentFlag {
|
|
v.LowDelayHrdFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
v.PicStructPresentFlag, err = bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
bitstreamRestrictionFlag, err := bits.ReadFlag(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if bitstreamRestrictionFlag {
|
|
v.BitstreamRestriction = &SPS_BitstreamRestriction{}
|
|
err := v.BitstreamRestriction.unmarshal(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// SPS_FrameCropping is the frame cropping part of a SPS.
|
|
type SPS_FrameCropping struct { //nolint:revive
|
|
LeftOffset uint32
|
|
RightOffset uint32
|
|
TopOffset uint32
|
|
BottomOffset uint32
|
|
}
|
|
|
|
func (c *SPS_FrameCropping) unmarshal(buf []byte, pos *int) error {
|
|
var err error
|
|
c.LeftOffset, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
c.RightOffset, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
c.TopOffset, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
c.BottomOffset, err = bits.ReadGolombUnsigned(buf, pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// SPS is a H264 sequence parameter set.
|
|
type SPS struct {
|
|
ProfileIdc uint8
|
|
ConstraintSet0Flag bool
|
|
ConstraintSet1Flag bool
|
|
ConstraintSet2Flag bool
|
|
ConstraintSet3Flag bool
|
|
ConstraintSet4Flag bool
|
|
ConstraintSet5Flag bool
|
|
LevelIdc uint8
|
|
ID uint32
|
|
|
|
// only for selected ProfileIdcs
|
|
ChromeFormatIdc uint32
|
|
SeparateColourPlaneFlag bool
|
|
BitDepthLumaMinus8 uint32
|
|
BitDepthChromaMinus8 uint32
|
|
QpprimeYZeroTransformBypassFlag bool
|
|
|
|
// seqScalingListPresentFlag == true
|
|
ScalingList4x4 [][]int32
|
|
UseDefaultScalingMatrix4x4Flag []bool
|
|
ScalingList8x8 [][]int32
|
|
UseDefaultScalingMatrix8x8Flag []bool
|
|
|
|
Log2MaxFrameNumMinus4 uint32
|
|
PicOrderCntType uint32
|
|
|
|
// PicOrderCntType == 0
|
|
Log2MaxPicOrderCntLsbMinus4 uint32
|
|
|
|
// PicOrderCntType == 1
|
|
DeltaPicOrderAlwaysZeroFlag bool
|
|
OffsetForNonRefPic int32
|
|
OffsetForTopToBottomField int32
|
|
OffsetForRefFrames []int32
|
|
|
|
MaxNumRefFrames uint32
|
|
GapsInFrameNumValueAllowedFlag bool
|
|
PicWidthInMbsMinus1 uint32
|
|
PicHeightInMapUnitsMinus1 uint32
|
|
FrameMbsOnlyFlag bool
|
|
|
|
// FrameMbsOnlyFlag == false
|
|
MbAdaptiveFrameFieldFlag bool
|
|
|
|
Direct8x8InferenceFlag bool
|
|
FrameCropping *SPS_FrameCropping
|
|
VUI *SPS_VUI
|
|
}
|
|
|
|
// Unmarshal decodes a SPS from bytes.
|
|
func (s *SPS) Unmarshal(buf []byte) error {
|
|
buf = EmulationPreventionRemove(buf)
|
|
|
|
if len(buf) < 4 {
|
|
return fmt.Errorf("not enough bits")
|
|
}
|
|
|
|
s.ProfileIdc = buf[1]
|
|
s.ConstraintSet0Flag = (buf[2] >> 7) == 1
|
|
s.ConstraintSet1Flag = (buf[2] >> 6 & 0x01) == 1
|
|
s.ConstraintSet2Flag = (buf[2] >> 5 & 0x01) == 1
|
|
s.ConstraintSet3Flag = (buf[2] >> 4 & 0x01) == 1
|
|
s.ConstraintSet4Flag = (buf[2] >> 3 & 0x01) == 1
|
|
s.ConstraintSet5Flag = (buf[2] >> 2 & 0x01) == 1
|
|
s.LevelIdc = buf[3]
|
|
|
|
buf = buf[4:]
|
|
pos := 0
|
|
|
|
var err error
|
|
s.ID, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
switch s.ProfileIdc {
|
|
case 100, 110, 122, 244, 44, 83, 86, 118, 128, 138, 139, 134, 135:
|
|
s.ChromeFormatIdc, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if s.ChromeFormatIdc == 3 {
|
|
s.SeparateColourPlaneFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
} else {
|
|
s.SeparateColourPlaneFlag = false
|
|
}
|
|
|
|
s.BitDepthLumaMinus8, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.BitDepthChromaMinus8, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.QpprimeYZeroTransformBypassFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
seqScalingMatrixPresentFlag, err := bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if seqScalingMatrixPresentFlag {
|
|
var lim int
|
|
if s.ChromeFormatIdc != 3 {
|
|
lim = 8
|
|
} else {
|
|
lim = 12
|
|
}
|
|
|
|
for i := 0; i < lim; i++ {
|
|
seqScalingListPresentFlag, err := bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if seqScalingListPresentFlag {
|
|
if i < 6 {
|
|
scalingList, useDefaultScalingMatrixFlag, err := readScalingList(buf, &pos, 16)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.ScalingList4x4 = append(s.ScalingList4x4, scalingList)
|
|
s.UseDefaultScalingMatrix4x4Flag = append(s.UseDefaultScalingMatrix4x4Flag,
|
|
useDefaultScalingMatrixFlag)
|
|
} else {
|
|
scalingList, useDefaultScalingMatrixFlag, err := readScalingList(buf, &pos, 64)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.ScalingList8x8 = append(s.ScalingList8x8, scalingList)
|
|
s.UseDefaultScalingMatrix8x8Flag = append(s.UseDefaultScalingMatrix8x8Flag,
|
|
useDefaultScalingMatrixFlag)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
default:
|
|
s.ChromeFormatIdc = 0
|
|
s.SeparateColourPlaneFlag = false
|
|
s.BitDepthLumaMinus8 = 0
|
|
s.BitDepthChromaMinus8 = 0
|
|
s.QpprimeYZeroTransformBypassFlag = false
|
|
}
|
|
|
|
s.Log2MaxFrameNumMinus4, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.PicOrderCntType, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
switch s.PicOrderCntType {
|
|
case 0:
|
|
s.Log2MaxPicOrderCntLsbMinus4, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.DeltaPicOrderAlwaysZeroFlag = false
|
|
s.OffsetForNonRefPic = 0
|
|
s.OffsetForTopToBottomField = 0
|
|
s.OffsetForRefFrames = nil
|
|
|
|
case 1:
|
|
s.Log2MaxPicOrderCntLsbMinus4 = 0
|
|
|
|
s.DeltaPicOrderAlwaysZeroFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.OffsetForNonRefPic, err = bits.ReadGolombSigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.OffsetForTopToBottomField, err = bits.ReadGolombSigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
numRefFramesInPicOrderCntCycle, err := bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if numRefFramesInPicOrderCntCycle > maxRefFrames {
|
|
return fmt.Errorf("num_ref_frames_in_pic_order_cnt_cycle exceeds %d", maxRefFrames)
|
|
}
|
|
|
|
s.OffsetForRefFrames = make([]int32, numRefFramesInPicOrderCntCycle)
|
|
for i := uint32(0); i < numRefFramesInPicOrderCntCycle; i++ {
|
|
v, err := bits.ReadGolombSigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.OffsetForRefFrames[i] = v
|
|
}
|
|
|
|
case 2:
|
|
s.Log2MaxPicOrderCntLsbMinus4 = 0
|
|
s.DeltaPicOrderAlwaysZeroFlag = false
|
|
s.OffsetForNonRefPic = 0
|
|
s.OffsetForTopToBottomField = 0
|
|
s.OffsetForRefFrames = nil
|
|
|
|
default:
|
|
return fmt.Errorf("invalid pic_order_cnt_type: %d", s.PicOrderCntType)
|
|
}
|
|
|
|
s.MaxNumRefFrames, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.GapsInFrameNumValueAllowedFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.PicWidthInMbsMinus1, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.PicHeightInMapUnitsMinus1, err = bits.ReadGolombUnsigned(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
s.FrameMbsOnlyFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if !s.FrameMbsOnlyFlag {
|
|
s.MbAdaptiveFrameFieldFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
} else {
|
|
s.MbAdaptiveFrameFieldFlag = false
|
|
}
|
|
|
|
s.Direct8x8InferenceFlag, err = bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
frameCroppingFlag, err := bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if frameCroppingFlag {
|
|
s.FrameCropping = &SPS_FrameCropping{}
|
|
err := s.FrameCropping.unmarshal(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
} else {
|
|
s.FrameCropping = nil
|
|
}
|
|
|
|
vuiParametersPresentFlag, err := bits.ReadFlag(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if vuiParametersPresentFlag {
|
|
s.VUI = &SPS_VUI{}
|
|
err := s.VUI.unmarshal(buf, &pos)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
} else {
|
|
s.VUI = nil
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Width returns the video width.
|
|
func (s SPS) Width() int {
|
|
if s.FrameCropping != nil {
|
|
return int(((s.PicWidthInMbsMinus1 + 1) * 16) - (s.FrameCropping.LeftOffset+s.FrameCropping.RightOffset)*2)
|
|
}
|
|
|
|
return int((s.PicWidthInMbsMinus1 + 1) * 16)
|
|
}
|
|
|
|
// Height returns the video height.
|
|
func (s SPS) Height() int {
|
|
f := uint32(0)
|
|
if s.FrameMbsOnlyFlag {
|
|
f = 1
|
|
}
|
|
|
|
if s.FrameCropping != nil {
|
|
return int(((2 - f) * (s.PicHeightInMapUnitsMinus1 + 1) * 16) -
|
|
(s.FrameCropping.TopOffset+s.FrameCropping.BottomOffset)*2)
|
|
}
|
|
|
|
return int((2 - f) * (s.PicHeightInMapUnitsMinus1 + 1) * 16)
|
|
}
|
|
|
|
// FPS returns the frames per second of the video.
|
|
func (s SPS) FPS() float64 {
|
|
if s.VUI == nil || s.VUI.TimingInfo == nil {
|
|
return 0
|
|
}
|
|
|
|
return float64(s.VUI.TimingInfo.TimeScale) / (2 * float64(s.VUI.TimingInfo.NumUnitsInTick))
|
|
}
|