feat(ffmpeg): select frame by duration and float position (#40)

* seek duration private

* feat(ffmpeg): select frame by duration and float position

ffmpeg/ffmpeg.go

@@ -41,6 +41,7 @@ type AVContext struct {
 	codecContext       *C.AVCodecContext
 	thumbContext       *C.ThumbContext
 	selectedIndex      C.int
+	selectedDuration   time.Duration
 	frame              *C.AVFrame
 	durationInFormat   bool
 	orientation        int
@@ -109,15 +110,7 @@ func (av *AVContext) SelectDuration(ts time.Duration) (err error) {
 			return
 		}
 	}
-	return av.SelectFrame(1)
-}
-
-func (av *AVContext) SeekPosition(f float64) (err error) {
-	return av.SeekDuration(av.positionToDuration(f))
-}
-
-func (av *AVContext) SeekDuration(ts time.Duration) (err error) {
-	return seekDuration(av, ts)
+	return av.ProcessFrames(-1)
 }
 
 func (av *AVContext) Export(bands int) (buf []byte, err error) {
@@ -234,6 +227,7 @@ func createDecoder(av *AVContext) error {
 }
 
 func seekDuration(av *AVContext, ts time.Duration) error {
+	av.selectedDuration = ts
 	tts := C.int64_t(ts.Milliseconds()) * C.AV_TIME_BASE / 1000
 	err := C.av_seek_frame(av.formatContext, C.int(-1), tts, C.AVSEEK_FLAG_BACKWARD)
 	C.avcodec_flush_buffers(av.codecContext)
@@ -249,6 +243,9 @@ func incrementDuration(av *AVContext, frame *C.AVFrame, i C.int) {
 		ptsToNano := C.int64_t(1000000000 * av.stream.time_base.num / av.stream.time_base.den)
 		newDuration := time.Duration(frame.pts * ptsToNano)
 		av.availableDuration = newDuration
+		if av.selectedDuration > 0 && i > 0 && newDuration <= av.selectedDuration {
+			av.selectedIndex = i
+		}
 		if !av.durationInFormat && newDuration > av.duration {
 			av.duration = newDuration
 		}
@@ -304,6 +301,9 @@ func createThumbContext(av *AVContext, maxFrames C.int) error {
 	if av.selectedIndex > -1 && n > av.selectedIndex+1 {
 		n = av.selectedIndex + 1
 	}
+	if av.selectedDuration > 0 && av.selectedIndex < 0 {
+		av.selectedIndex = 0
+	}
 	frames := make(chan *C.AVFrame, n)
 	done := populateFrames(av, frames)
 	frames <- frame

ffmpeg/ffmpeg_test.go

@@ -13,6 +13,7 @@ import (
 	"reflect"
 	"strings"
 	"testing"
+	"time"
 )
 
 var files = []string{
@@ -71,7 +72,7 @@ func TestAVContext(t *testing.T) {
 				if n == 10 {
 					require.NoError(t, av.ProcessFrames(n))
 				} else if n == 99999 {
-					require.NoError(t, av.SeekPosition(0.6))
+					require.NoError(t, av.SelectDuration(time.Millisecond*500))
 				} else if n == 9999 {
 					require.NoError(t, av.SelectPosition(0.7))
 				} else if n > -1 {

processor.go

@@ -125,16 +125,6 @@ func (p *Processor) Process(ctx context.Context, in *imagor.Blob, params imagorp
 					bands = 4
 				}
 			}
-		case "seek":
-			if ts, e := time.ParseDuration(filter.Args); e == nil {
-				if err = av.SeekDuration(ts); err != nil {
-					return
-				}
-			} else if f, e := strconv.ParseFloat(filter.Args, 64); e == nil {
-				if err = av.SeekPosition(f); err != nil {
-					return
-				}
-			}
 		case "frame":
 			if ts, e := time.ParseDuration(filter.Args); e == nil {
 				if err = av.SelectDuration(ts); err != nil {

processor_test.go

@@ -57,8 +57,6 @@ func TestProcessor(t *testing.T) {
 		{name: "alpha", path: "fit-in/filters:format(png)/alpha-webm.webm"},
 		{name: "alpha frame duration", path: "500x/filters:frame(5s):format(png)/alpha-webm.webm", sizeOnly: true},
 		{name: "alpha frame position", path: "500x/filters:frame(0.5):format(png)/alpha-webm.webm", sizeOnly: true},
-		{name: "alpha seek duration", path: "500x/filters:seek(5s):format(png)/alpha-webm.webm", sizeOnly: true},
-		{name: "alpha seek position", path: "500x/filters:seek(0.5):format(png)/alpha-webm.webm", sizeOnly: true},
 		{name: "corrupted", path: "fit-in/100x100/corrupt/everybody-betray-me.mkv", expectCode: 406},
 		{name: "no cover meta", path: "meta/no_cover.mp3"},
 		{name: "no cover 406", path: "fit-in/100x100/no_cover.mp3", expectCode: 406},

testdata/golden/meta/alpha-webm.webm-9999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":12040,"width":720,"height":576,"has_video":true,"has_audio":false}
+{"orientation":1,"duration":12040,"width":720,"height":576,"fps":10.9,"has_video":true,"has_audio":false}

testdata/golden/meta/alpha-webm.webm-99999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":12040,"width":720,"height":576,"has_video":true,"has_audio":false}
+{"orientation":1,"duration":12040,"width":720,"height":576,"fps":25,"has_video":true,"has_audio":false}

testdata/golden/meta/everybody-betray-me.mkv-9999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":7407,"width":640,"height":480,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":7407,"width":640,"height":480,"fps":9.3,"has_video":true,"has_audio":true}

testdata/golden/meta/everybody-betray-me.mkv-99999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":7407,"width":640,"height":480,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":7407,"width":640,"height":480,"fps":26.3,"has_video":true,"has_audio":true}

testdata/golden/meta/macabre.mp4-9999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":3925,"width":492,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":3925,"width":492,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/macabre.mp4-99999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":3925,"width":492,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":3925,"width":492,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo.flv-9999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":2560,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":2560,"width":480,"height":360,"fps":29.7,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo.flv-99999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":2560,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":2560,"width":480,"height":360,"fps":29.7,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_0.mp4-9999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":2544,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":2544,"width":480,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_0.mp4-99999.meta.json

@@ -1 +1 @@
-{"orientation":1,"duration":2544,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":1,"duration":2544,"width":480,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_180.mp4-9999.meta.json

@@ -1 +1 @@
-{"orientation":3,"duration":2544,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":3,"duration":2544,"width":480,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_180.mp4-99999.meta.json

@@ -1 +1 @@
-{"orientation":3,"duration":2544,"width":480,"height":360,"has_video":true,"has_audio":true}
+{"orientation":3,"duration":2544,"width":480,"height":360,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_270.mp4-9999.meta.json

@@ -1 +1 @@
-{"orientation":6,"duration":2544,"width":360,"height":480,"has_video":true,"has_audio":true}
+{"orientation":6,"duration":2544,"width":360,"height":480,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_270.mp4-99999.meta.json

@@ -1 +1 @@
-{"orientation":6,"duration":2544,"width":360,"height":480,"has_video":true,"has_audio":true}
+{"orientation":6,"duration":2544,"width":360,"height":480,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_90.mp4-9999.meta.json

@@ -1 +1 @@
-{"orientation":8,"duration":2544,"width":360,"height":480,"has_video":true,"has_audio":true}
+{"orientation":8,"duration":2544,"width":360,"height":480,"fps":30,"has_video":true,"has_audio":true}

testdata/golden/meta/schizo_90.mp4-99999.meta.json

@@ -1 +1 @@
-{"orientation":8,"duration":2544,"width":360,"height":480,"has_video":true,"has_audio":true}
+{"orientation":8,"duration":2544,"width":360,"height":480,"fps":30,"has_video":true,"has_audio":true}