OpenMediaCenter/apiGo/videoparser/thumbnail/Thumbnailparser_shared_ffmpeg.go

199 lines
4.1 KiB
Go

// +build sharedffmpeg
package thumbnail
import (
"fmt"
"github.com/3d0c/gmf"
"io"
"log"
"os"
)
func Parse(filename string, time uint64) (*string, *VidInfo, error) {
dta, inf, err := decodePic(filename, "mjpeg", time)
if err == nil && dta != nil {
// base64 encode picture
enc := EncodeBase64(dta, "image/jpeg")
return enc, inf, nil
} else {
return nil, nil, err
}
}
func decodePic(srcFileName string, encodeExtension string, time uint64) (pic *[]byte, info *VidInfo, err error) {
var swsctx *gmf.SwsCtx
gmf.LogSetLevel(gmf.AV_LOG_PANIC)
stat, err := os.Stat(srcFileName)
if err != nil {
// file seems to not even exist
return nil, nil, err
}
fileSize := stat.Size()
inputCtx, err := gmf.NewInputCtx(srcFileName)
if err != nil {
log.Printf("Error creating context - %s\n", err)
return nil, nil, err
}
defer inputCtx.Free()
srcVideoStream, err := inputCtx.GetBestStream(gmf.AVMEDIA_TYPE_VIDEO)
if err != nil {
log.Printf("No video stream found in '%s'\n", srcFileName)
return nil, nil, err
}
encodeCodec, err := gmf.FindEncoder(encodeExtension)
if err != nil {
log.Printf("%s\n", err)
return nil, nil, err
}
cc := gmf.NewCodecCtx(encodeCodec)
defer gmf.Release(cc)
cc.SetTimeBase(gmf.AVR{Num: 1, Den: 1})
cc.SetPixFmt(gmf.AV_PIX_FMT_YUVJ444P).SetWidth(srcVideoStream.CodecPar().Width()).SetHeight(srcVideoStream.CodecPar().Height())
if encodeCodec.IsExperimental() {
cc.SetStrictCompliance(gmf.FF_COMPLIANCE_EXPERIMENTAL)
}
if err := cc.Open(nil); err != nil {
log.Println(err)
return nil, nil, err
}
defer cc.Free()
err = inputCtx.SeekFrameAt(int64(time), srcVideoStream.Index())
if err != nil {
log.Printf("Error while seeking file: %s\n", err.Error())
return nil, nil, err
}
// find encodeCodec to decode video
decodeCodec, err := gmf.FindDecoder(srcVideoStream.CodecPar().CodecId())
if err != nil {
fmt.Println(err)
return nil, nil, err
}
icc := gmf.NewCodecCtx(decodeCodec)
defer gmf.Release(icc)
// copy stream parameters in codeccontext
err = srcVideoStream.CodecPar().ToContext(icc)
if err != nil {
fmt.Println(err.Error())
}
// convert source pix_fmt into AV_PIX_FMT_RGBA
if swsctx, err = gmf.NewSwsCtx(icc.Width(), icc.Height(), icc.PixFmt(), cc.Width(), cc.Height(), cc.PixFmt(), gmf.SWS_BICUBIC); err != nil {
panic(err)
}
defer swsctx.Free()
frameRate := float32(srcVideoStream.GetRFrameRate().AVR().Num) / float32(srcVideoStream.GetRFrameRate().AVR().Den)
inf := VidInfo{
Width: uint32(icc.Width()),
Height: uint32(icc.Height()),
FrameRate: frameRate,
Length: uint64(inputCtx.Duration()),
Size: fileSize,
}
info = &inf
var (
pkt *gmf.Packet
frames []*gmf.Frame
drain int = -1
frameCount int = 0
)
for {
if drain >= 0 {
break
}
pkt, err = inputCtx.GetNextPacket()
if err != nil && err != io.EOF {
if pkt != nil {
pkt.Free()
}
log.Printf("error getting next packet - %s", err)
break
} else if err != nil && pkt == nil {
drain = 0
}
if pkt != nil && pkt.StreamIndex() != srcVideoStream.Index() {
continue
}
frames, err = srcVideoStream.CodecCtx().Decode(pkt)
if err != nil {
log.Printf("Fatal error during decoding - %s\n", err)
break
}
// Decode() method doesn't treat EAGAIN and EOF as errors
// it returns empty frames slice instead. Countinue until
// input EOF or frames received.
if len(frames) == 0 && drain < 0 {
continue
}
if frames, err = gmf.DefaultRescaler(swsctx, frames); err != nil {
panic(err)
}
packets, err := cc.Encode(frames, drain)
if len(packets) == 0 {
continue
}
if err != nil {
continue
}
picdata := packets[0].Data()
pic = &picdata
// cleanup here
for _, p := range packets {
p.Free()
}
for i := range frames {
frames[i].Free()
frameCount++
}
if pkt != nil {
pkt.Free()
pkt = nil
}
// we only want to encode first picture then exit
break
}
for i := 0; i < inputCtx.StreamsCnt(); i++ {
st, err := inputCtx.GetStream(i)
if err == nil && st != nil {
st.Free()
}
}
icc.Free()
srcVideoStream.Free()
return
}