292 lines
6.5 KiB
Go
292 lines
6.5 KiB
Go
package y4m
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"git.gammaspectra.live/S.O.N.G/Ignite/colorspace"
|
|
"git.gammaspectra.live/S.O.N.G/Ignite/frame"
|
|
"git.gammaspectra.live/S.O.N.G/Ignite/utilities"
|
|
"io"
|
|
"strconv"
|
|
"strings"
|
|
)
|
|
|
|
type Stream struct {
|
|
r io.Reader
|
|
frameSeekTable []int64
|
|
parameters map[Parameter][]string
|
|
|
|
width int
|
|
height int
|
|
frameRate utilities.Ratio
|
|
pixelAspectRatio utilities.Ratio
|
|
colorSpace colorspace.ColorSpace
|
|
colorRangeFull bool
|
|
|
|
frameSize int
|
|
|
|
frameCounter int
|
|
}
|
|
|
|
type Parameter byte
|
|
|
|
const (
|
|
ParameterFrameWidth Parameter = 'W'
|
|
ParameterFrameHeight Parameter = 'H'
|
|
ParameterFrameRate Parameter = 'F'
|
|
ParameterInterlacing Parameter = 'I'
|
|
ParameterPixelAspectRatio Parameter = 'A'
|
|
ParameterColorSpace Parameter = 'C'
|
|
ParameterExtension Parameter = 'X'
|
|
)
|
|
|
|
const fileMagic = "YUV4MPEG2 "
|
|
const frameMagic = "FRAME"
|
|
|
|
func New(reader io.Reader) (*Stream, error) {
|
|
s := &Stream{
|
|
r: reader,
|
|
parameters: make(map[Parameter][]string),
|
|
}
|
|
|
|
if err := s.readHeader(); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if err := s.parseParameters(); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return s, nil
|
|
}
|
|
|
|
func (s *Stream) Resolution() (width, height int) {
|
|
return s.width, s.height
|
|
}
|
|
|
|
func (s *Stream) FrameRate() utilities.Ratio {
|
|
return s.frameRate
|
|
}
|
|
|
|
func (s *Stream) ColorSpace() colorspace.ColorSpace {
|
|
return s.colorSpace
|
|
}
|
|
|
|
func (s *Stream) ColorRange() bool {
|
|
return s.colorRangeFull
|
|
}
|
|
|
|
func (s *Stream) PixelAspectRatio() utilities.Ratio {
|
|
return s.pixelAspectRatio
|
|
}
|
|
|
|
func (s *Stream) SeekToFrame(frameNumber int) (err error) {
|
|
if seeker, ok := s.r.(io.Seeker); ok {
|
|
if frameNumber >= 0 && len(s.frameSeekTable) > frameNumber && s.frameSeekTable[frameNumber] != 0 {
|
|
if _, err = seeker.Seek(s.frameSeekTable[frameNumber], io.SeekStart); err != nil {
|
|
return err
|
|
}
|
|
|
|
s.frameCounter = frameNumber
|
|
|
|
return nil
|
|
} else {
|
|
return errors.New("frameNumber out of range")
|
|
}
|
|
} else {
|
|
return errors.New("reader is not io.Seeker")
|
|
}
|
|
}
|
|
|
|
func (s *Stream) GetFrame() (frameNumber int, parameters map[Parameter][]string, frameObject frame.Frame, err error) {
|
|
var index int64
|
|
|
|
frameNumber = s.frameCounter
|
|
|
|
if seeker, ok := s.r.(io.Seeker); ok {
|
|
if index, err = seeker.Seek(0, io.SeekCurrent); err != nil {
|
|
return 0, nil, nil, err
|
|
}
|
|
}
|
|
|
|
if parameters, err = s.readFrameHeader(); err != nil {
|
|
return 0, nil, nil, err
|
|
}
|
|
|
|
if index > 0 {
|
|
for len(s.frameSeekTable) <= s.frameCounter {
|
|
s.frameSeekTable = append(s.frameSeekTable, 0)
|
|
}
|
|
s.frameSeekTable[s.frameCounter] = index
|
|
}
|
|
|
|
var buf []byte
|
|
if buf, err = s.readFrameData(); err != nil {
|
|
return 0, nil, nil, err
|
|
}
|
|
|
|
if s.colorSpace.BitDepth > 8 {
|
|
if frameObject, err = frame.NewUint16FrameFromBytes(s.colorSpace, s.width, s.height, buf); err != nil {
|
|
return 0, nil, nil, err
|
|
}
|
|
} else {
|
|
if frameObject, err = frame.NewUint8FrameFromBytes(s.colorSpace, s.width, s.height, buf); err != nil {
|
|
return 0, nil, nil, err
|
|
}
|
|
}
|
|
|
|
s.frameCounter++
|
|
|
|
return
|
|
}
|
|
|
|
func (s *Stream) readHeader() (err error) {
|
|
header := make([]byte, 10)
|
|
if _, err = io.ReadFull(s.r, header); err != nil {
|
|
return err
|
|
}
|
|
|
|
if string(header) != fileMagic {
|
|
return fmt.Errorf("invalid file signature, %s != %s", string(header), fileMagic)
|
|
}
|
|
|
|
data := make([]byte, 0, 1024)
|
|
buf := make([]byte, 1)
|
|
for {
|
|
if _, err = s.r.Read(buf); err != nil {
|
|
return err
|
|
}
|
|
|
|
if buf[0] == '\n' {
|
|
break
|
|
}
|
|
|
|
data = append(data, buf[0])
|
|
}
|
|
|
|
for _, v := range strings.Split(string(data), " ") {
|
|
if len(v) > 1 {
|
|
if slice, ok := s.parameters[Parameter(v[0])]; ok {
|
|
s.parameters[Parameter(v[0])] = append(slice, v[1:])
|
|
} else {
|
|
s.parameters[Parameter(v[0])] = []string{v[1:]}
|
|
}
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (s *Stream) readFrameHeader() (parameters map[Parameter][]string, err error) {
|
|
header := make([]byte, 5)
|
|
if _, err = io.ReadFull(s.r, header); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if string(header) != frameMagic {
|
|
return nil, fmt.Errorf("invalid frame signature, %s != %s", string(header), frameMagic)
|
|
}
|
|
|
|
var data []byte
|
|
buf := make([]byte, 1)
|
|
for {
|
|
if _, err = s.r.Read(buf); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if buf[0] == '\n' {
|
|
break
|
|
}
|
|
|
|
data = append(data, buf[0])
|
|
}
|
|
|
|
parameters = make(map[Parameter][]string)
|
|
|
|
for _, v := range strings.Split(string(data), " ") {
|
|
if len(v) > 1 {
|
|
if slice, ok := parameters[Parameter(v[0])]; ok {
|
|
parameters[Parameter(v[0])] = append(slice, v[1:])
|
|
} else {
|
|
parameters[Parameter(v[0])] = []string{v[1:]}
|
|
}
|
|
}
|
|
}
|
|
|
|
return parameters, nil
|
|
}
|
|
|
|
func (s *Stream) readFrameData() (buf []byte, err error) {
|
|
//TODO: reuse buffers, maybe channel?
|
|
buf = make([]byte, s.frameSize)
|
|
_, err = io.ReadFull(s.r, buf)
|
|
return buf, err
|
|
}
|
|
|
|
func (s *Stream) parseParameters() (err error) {
|
|
for k, values := range s.parameters {
|
|
switch k {
|
|
case ParameterFrameWidth:
|
|
if s.width, err = strconv.Atoi(values[0]); err != nil {
|
|
return err
|
|
}
|
|
case ParameterFrameHeight:
|
|
if s.height, err = strconv.Atoi(values[0]); err != nil {
|
|
return err
|
|
}
|
|
case ParameterFrameRate:
|
|
v := strings.Split(values[0], ":")
|
|
if len(v) != 2 {
|
|
return fmt.Errorf("wrong frame rate %s", values[0])
|
|
}
|
|
if s.frameRate.Numerator, err = strconv.Atoi(v[0]); err != nil {
|
|
return err
|
|
}
|
|
if s.frameRate.Denominator, err = strconv.Atoi(v[1]); err != nil {
|
|
return err
|
|
}
|
|
case ParameterInterlacing:
|
|
if values[0] != "p" {
|
|
return fmt.Errorf("not supported interlacing %s", values[0])
|
|
}
|
|
case ParameterPixelAspectRatio:
|
|
v := strings.Split(values[0], ":")
|
|
if len(v) != 2 {
|
|
return fmt.Errorf("wrong pixel aspect ratio %s", values[0])
|
|
}
|
|
if s.pixelAspectRatio.Numerator, err = strconv.Atoi(v[0]); err != nil {
|
|
return err
|
|
}
|
|
if s.pixelAspectRatio.Denominator, err = strconv.Atoi(v[1]); err != nil {
|
|
return err
|
|
}
|
|
case ParameterColorSpace:
|
|
if s.colorSpace, err = colorspace.NewColorSpaceFromString(values[0]); err != nil {
|
|
return err
|
|
}
|
|
case ParameterExtension:
|
|
for _, v := range values {
|
|
extVal := strings.Split(v, "=")
|
|
if len(extVal) >= 2 {
|
|
switch extVal[0] {
|
|
case "COLORRANGE":
|
|
if extVal[1] == "FULL" {
|
|
s.colorRangeFull = true
|
|
} else if extVal[1] == "LIMITED" {
|
|
s.colorRangeFull = false
|
|
} else {
|
|
return fmt.Errorf("not supported %s: %s", extVal[0], extVal[1])
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
//TODO: check for missing values width, height, colorspace etc.
|
|
|
|
s.frameSize, err = s.colorSpace.FrameSize(s.width, s.height)
|
|
|
|
return err
|
|
}
|