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| 1 | +package video_player |
| 2 | + |
| 3 | +// This file hides the ffmpeg related computations. |
| 4 | +// |
| 5 | +// The api exposed by github.com/3d0c/gmf is messy (all go-ffmpeg lib are) |
| 6 | +// which explain the following mess. |
| 7 | +// |
| 8 | +// Be very careful when you make changes to this file. |
| 9 | +// |
| 10 | +// Based on the examples 'video-to-goImage.go' of 3d0c/gmf. |
| 11 | +// TODO: fix the memory leak will occur.. |
| 12 | +import ( |
| 13 | + "errors" |
| 14 | + "fmt" |
| 15 | + "io" |
| 16 | + "sync" |
| 17 | + "sync/atomic" |
| 18 | + |
| 19 | + "github.com/3d0c/gmf" |
| 20 | +) |
| 21 | + |
| 22 | +// #include "libavformat/avformat.h" |
| 23 | +import "C" |
| 24 | + |
| 25 | +type ffmpegVideo struct { |
| 26 | + swsctx *gmf.SwsCtx |
| 27 | + ist *gmf.Stream |
| 28 | + cc *gmf.CodecCtx |
| 29 | + inputCtx *gmf.FmtCtx |
| 30 | + srcVideoStream *gmf.Stream |
| 31 | + Frames chan *ffmpegFrame |
| 32 | + paused chan bool |
| 33 | + player *playerStatus |
| 34 | + pausedFlag bool |
| 35 | + width int |
| 36 | + height int |
| 37 | +} |
| 38 | + |
| 39 | +type ffmpegFrame struct { |
| 40 | + // ffmpeg packet |
| 41 | + packet *gmf.Packet |
| 42 | + // in second |
| 43 | + time float64 |
| 44 | +} |
| 45 | + |
| 46 | +func (f *ffmpegFrame) Time() float64 { |
| 47 | + return f.time |
| 48 | +} |
| 49 | + |
| 50 | +func (f *ffmpegFrame) Data() []byte { |
| 51 | + return f.packet.Data() |
| 52 | +} |
| 53 | + |
| 54 | +func (f *ffmpegFrame) Free() { |
| 55 | + f.packet.Free() |
| 56 | +} |
| 57 | + |
| 58 | +type playerStatus struct{ flag int32 } |
| 59 | + |
| 60 | +const ( |
| 61 | + allImagesProcessed = 2 |
| 62 | + playing = 1 |
| 63 | + noImagesAvailable = 0 |
| 64 | +) |
| 65 | + |
| 66 | +func (f *ffmpegVideo) Init(srcFileName string, bufferSize int) (err error) { |
| 67 | + f.player = new(playerStatus) |
| 68 | + f.paused = make(chan bool) |
| 69 | + |
| 70 | + f.inputCtx, err = gmf.NewInputCtx(srcFileName) |
| 71 | + f.Frames = make(chan *ffmpegFrame, bufferSize) |
| 72 | + |
| 73 | + f.srcVideoStream, err = f.inputCtx.GetBestStream(gmf.AVMEDIA_TYPE_VIDEO) |
| 74 | + if err != nil { |
| 75 | + return errors.New("No video stream found in " + srcFileName + "\n") |
| 76 | + } |
| 77 | + |
| 78 | + codec, err := gmf.FindEncoder(gmf.AV_CODEC_ID_RAWVIDEO) |
| 79 | + if err != nil { |
| 80 | + return err |
| 81 | + } |
| 82 | + |
| 83 | + f.cc = gmf.NewCodecCtx(codec) |
| 84 | + |
| 85 | + f.cc. |
| 86 | + SetTimeBase(gmf.AVR{Num: 1, Den: 1}). |
| 87 | + SetPixFmt(gmf.AV_PIX_FMT_RGBA). |
| 88 | + SetWidth(f.srcVideoStream.CodecCtx().Width()). |
| 89 | + SetHeight(f.srcVideoStream.CodecCtx().Height()) |
| 90 | + |
| 91 | + f.width, f.height = f.cc.Width(), f.cc.Height() |
| 92 | + |
| 93 | + if codec.IsExperimental() { |
| 94 | + f.cc.SetStrictCompliance(gmf.FF_COMPLIANCE_EXPERIMENTAL) |
| 95 | + } |
| 96 | + |
| 97 | + if err := f.cc.Open(nil); err != nil { |
| 98 | + return err |
| 99 | + } |
| 100 | + |
| 101 | + f.ist, err = f.inputCtx.GetStream(f.srcVideoStream.Index()) |
| 102 | + if err != nil { |
| 103 | + return err |
| 104 | + } |
| 105 | + |
| 106 | + // convert source pix_fmt into AV_PIX_FMT_RGBA |
| 107 | + // which is set up by codec context above |
| 108 | + icc := f.srcVideoStream.CodecCtx() |
| 109 | + if f.swsctx, err = gmf.NewSwsCtx(icc.Width(), icc.Height(), icc.PixFmt(), f.cc.Width(), f.cc.Height(), f.cc.PixFmt(), gmf.SWS_BICUBIC); err != nil { |
| 110 | + return err |
| 111 | + } |
| 112 | + |
| 113 | + return nil |
| 114 | +} |
| 115 | + |
| 116 | +func (f *ffmpegVideo) Free() { |
| 117 | + f.Cancel() |
| 118 | + f.srcVideoStream.Free() |
| 119 | + f.swsctx.Free() |
| 120 | + f.ist.Free() |
| 121 | + f.inputCtx.Free() |
| 122 | + gmf.Release(f.cc) |
| 123 | + f.cc.Free() |
| 124 | + close(f.Frames) |
| 125 | +} |
| 126 | + |
| 127 | +func (f *ffmpegVideo) Stream(onFirstFrame func()) { |
| 128 | + drain := -1 |
| 129 | + hasConsumer := false |
| 130 | + var wg sync.WaitGroup |
| 131 | + |
| 132 | + defer func() { |
| 133 | + if r := recover(); r != nil { |
| 134 | + fmt.Println("go-flutter/plugins/video_player: recover: ", r) |
| 135 | + for len(f.Frames) > 0 { // clean the frame channel |
| 136 | + pixels := <-f.Frames |
| 137 | + defer pixels.Free() |
| 138 | + } |
| 139 | + f.Cancel() |
| 140 | + } |
| 141 | + }() |
| 142 | + |
| 143 | + for { |
| 144 | + if drain >= 0 { |
| 145 | + break |
| 146 | + } |
| 147 | + |
| 148 | + pkt, err := f.inputCtx.GetNextPacket() |
| 149 | + if err != nil && err != io.EOF { |
| 150 | + if pkt != nil { |
| 151 | + pkt.Free() |
| 152 | + } |
| 153 | + fmt.Printf("go-flutter/plugins/video_player: error getting next packet - %s\n", err) |
| 154 | + break |
| 155 | + } else if err != nil && pkt == nil { |
| 156 | + drain = 0 |
| 157 | + } |
| 158 | + |
| 159 | + if pkt != nil && pkt.StreamIndex() != f.srcVideoStream.Index() { |
| 160 | + continue |
| 161 | + } |
| 162 | + |
| 163 | + frames, err := f.ist.CodecCtx().Decode(pkt) |
| 164 | + if err != nil { |
| 165 | + fmt.Printf("go-flutter/plugins/video_player: Fatal error during decoding - %s\n", err) |
| 166 | + break |
| 167 | + } |
| 168 | + |
| 169 | + // Decode() method doesn't treat EAGAIN and EOF as errors |
| 170 | + // it returns empty frames slice instead. Countinue until |
| 171 | + // input EOF or frames received. |
| 172 | + if len(frames) == 0 && drain < 0 { |
| 173 | + continue |
| 174 | + } |
| 175 | + |
| 176 | + if frames, err = gmf.DefaultRescaler(f.swsctx, frames); err != nil { |
| 177 | + panic(err) |
| 178 | + } |
| 179 | + |
| 180 | + packets, err := f.cc.Encode(frames, drain) |
| 181 | + if err != nil { |
| 182 | + fmt.Printf("go-flutter/plugins/video_player: Error encoding - %s\n", err) |
| 183 | + panic(err) |
| 184 | + } |
| 185 | + |
| 186 | + for _, p := range packets { |
| 187 | + |
| 188 | + if f.Closed() && hasConsumer { |
| 189 | + break |
| 190 | + } |
| 191 | + |
| 192 | + timebase := f.srcVideoStream.TimeBase() |
| 193 | + time := float64(timebase.AVR().Num) / float64(timebase.AVR().Den) * float64(p.Pts()) |
| 194 | + f.Frames <- &ffmpegFrame{packet: p, time: time} |
| 195 | + if !hasConsumer { |
| 196 | + f.play() |
| 197 | + wg.Add(1) |
| 198 | + go func() { |
| 199 | + onFirstFrame() |
| 200 | + wg.Done() |
| 201 | + }() |
| 202 | + hasConsumer = true |
| 203 | + } |
| 204 | + |
| 205 | + } |
| 206 | + |
| 207 | + for i := range frames { |
| 208 | + frames[i].Free() |
| 209 | + } |
| 210 | + |
| 211 | + if pkt != nil { |
| 212 | + pkt.Free() |
| 213 | + pkt = nil |
| 214 | + } |
| 215 | + } |
| 216 | + if !f.Closed() { |
| 217 | + f.EndOfVideo() |
| 218 | + } |
| 219 | + for i := 0; i < f.inputCtx.StreamsCnt(); i++ { |
| 220 | + st, _ := f.inputCtx.GetStream(i) |
| 221 | + defer st.CodecCtx().Free() |
| 222 | + defer st.Free() |
| 223 | + } |
| 224 | + |
| 225 | + wg.Wait() |
| 226 | +} |
| 227 | + |
| 228 | +func (f *ffmpegVideo) Bounds() (int, int) { |
| 229 | + return f.width, f.height |
| 230 | +} |
| 231 | + |
| 232 | +func (f *ffmpegVideo) GetFrameRate() float64 { |
| 233 | + a := f.srcVideoStream.GetRFrameRate().AVR() |
| 234 | + return float64(a.Den) / float64(a.Num) |
| 235 | +} |
| 236 | + |
| 237 | +func (f *ffmpegVideo) Duration() float64 { |
| 238 | + return f.inputCtx.Duration() |
| 239 | +} |
| 240 | + |
| 241 | +func (f *ffmpegVideo) EndOfVideo() { |
| 242 | + f.Set(allImagesProcessed) |
| 243 | +} |
| 244 | + |
| 245 | +func (f *ffmpegVideo) play() { |
| 246 | + f.Set(playing) |
| 247 | +} |
| 248 | + |
| 249 | +func (f *ffmpegVideo) Pause() { |
| 250 | + f.pausedFlag = true |
| 251 | +} |
| 252 | + |
| 253 | +func (f *ffmpegVideo) UnPause() { |
| 254 | + f.pausedFlag = false |
| 255 | + f.paused <- true |
| 256 | +} |
| 257 | + |
| 258 | +func (f *ffmpegVideo) Cancel() { |
| 259 | + f.Set(noImagesAvailable) |
| 260 | +} |
| 261 | + |
| 262 | +func (f *ffmpegVideo) Set(value int32) { |
| 263 | + atomic.StoreInt32(&(f.player.flag), value) |
| 264 | +} |
| 265 | + |
| 266 | +func (f *ffmpegVideo) Closed() bool { |
| 267 | + flag := atomic.LoadInt32(&(f.player.flag)) |
| 268 | + if flag == allImagesProcessed && len(f.Frames) <= 1 { |
| 269 | + defer f.Set(noImagesAvailable) |
| 270 | + } |
| 271 | + return flag != playing && len(f.Frames) == 0 |
| 272 | +} |
| 273 | + |
| 274 | +func (f *ffmpegVideo) HasFrameAvailable() bool { |
| 275 | + flag := atomic.LoadInt32(&(f.player.flag)) |
| 276 | + |
| 277 | + if flag == allImagesProcessed || flag == playing { |
| 278 | + return true |
| 279 | + } |
| 280 | + return false |
| 281 | +} |
| 282 | + |
| 283 | +func (f *ffmpegVideo) WaitUnPause() { |
| 284 | + if f.pausedFlag { |
| 285 | + <-f.paused |
| 286 | + } |
| 287 | +} |
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