From 387b74b62e9eb357ecca1aa31008830a37edbf4b Mon Sep 17 00:00:00 2001
From: Justyer <1554694323@qq.com>
Date: Thu, 12 Jun 2025 11:47:19 +0800
Subject: [PATCH] feat: snapshot frame_type add 2

---
 examples/ffmpeg/amix/main.go      | 41 +++++++++++++++++++++++++++++++
 examples/ffmpeg/concat/main.go    |  2 +-
 examples/service/snapshot/main.go |  5 ++--
 ffmpeg/ffmpeg.go                  | 11 ++++-----
 snapshot.go                       | 16 ++++++++++--
 snapshot_params.go                | 22 +++++++++++------
 6 files changed, 79 insertions(+), 18 deletions(-)
 create mode 100644 examples/ffmpeg/amix/main.go

diff --git a/examples/ffmpeg/amix/main.go b/examples/ffmpeg/amix/main.go
new file mode 100644
index 0000000..27b1ffc
--- /dev/null
+++ b/examples/ffmpeg/amix/main.go
@@ -0,0 +1,41 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/fxkt-tech/liv/ffmpeg"
+	"github.com/fxkt-tech/liv/ffmpeg/codec"
+	"github.com/fxkt-tech/liv/ffmpeg/filter"
+	"github.com/fxkt-tech/liv/ffmpeg/input"
+	"github.com/fxkt-tech/liv/ffmpeg/output"
+)
+
+func main() {
+	var (
+		ctx    = context.Background()
+		input1 = input.WithSimple("a1.aac")
+		input2 = input.WithSimple("a2.aac")
+		fAmix  = filter.AMix(2)
+	)
+
+	err := ffmpeg.New(
+		ffmpeg.WithLogLevel(""),
+		ffmpeg.WithDebug(true),
+		ffmpeg.WithDry(true),
+	).AddInput(
+		input1, input2,
+	).AddFilter(
+		fAmix,
+	).
+		AddOutput(
+			output.New(
+				output.Map(fAmix),
+				output.AudioCodec(codec.AAC),
+				output.File("out.mp4"),
+			),
+		).Run(ctx)
+	if err != nil {
+		fmt.Println(err)
+	}
+}
diff --git a/examples/ffmpeg/concat/main.go b/examples/ffmpeg/concat/main.go
index 6586b5d..9ecb102 100644
--- a/examples/ffmpeg/concat/main.go
+++ b/examples/ffmpeg/concat/main.go
@@ -19,7 +19,7 @@ func main() {
 	err := ffmpeg.New(
 		ffmpeg.WithLogLevel(""),
 		ffmpeg.WithDebug(true),
-	// ffmpeg.Dry(true),
+		ffmpeg.WithDry(true),
 	).AddInput(
 		input1,
 	).AddOutput(
diff --git a/examples/service/snapshot/main.go b/examples/service/snapshot/main.go
index abe4a33..c5ac9ff 100644
--- a/examples/service/snapshot/main.go
+++ b/examples/service/snapshot/main.go
@@ -15,8 +15,9 @@ func main() {
 			Infile:    "../../testdata/in.mp4",
 			Outfile:   "ss/simple-%05d.jpg",
 			StartTime: 0,
-			// FrameType: 1,
-			Num: 4,
+			FrameType: 2,
+			Frames:    []int32{1, 10, 300, 301},
+			// Num: 4,
 			// Interval: 5,
 			Width:  960,
 			Height: 540,
diff --git a/ffmpeg/ffmpeg.go b/ffmpeg/ffmpeg.go
index 9883b95..aa24f24 100644
--- a/ffmpeg/ffmpeg.go
+++ b/ffmpeg/ffmpeg.go
@@ -82,14 +82,13 @@ func (ff *FFmpeg) DryRun() {
 }
 
 func (ff *FFmpeg) Run(ctx context.Context) (err error) {
-	if ff.debug {
+	if ff.dry {
+		ff.DryRun()
+		return nil
+	} else if ff.debug {
 		ff.DryRun()
-	} else {
-		if ff.dry {
-			ff.DryRun()
-			return nil
-		}
 	}
+
 	cc := exec.CommandContext(ctx, ff.bin, ff.Params()...)
 	retbytes, err := cc.CombinedOutput()
 	if err != nil {
diff --git a/snapshot.go b/snapshot.go
index 4fe77a2..a56bed9 100644
--- a/snapshot.go
+++ b/snapshot.go
@@ -17,6 +17,7 @@ import (
 	"github.com/fxkt-tech/liv/ffmpeg/stream"
 	"github.com/fxkt-tech/liv/ffprobe"
 	"github.com/fxkt-tech/liv/pkg/math"
+	"github.com/fxkt-tech/liv/pkg/sugar"
 )
 
 type Snapshot struct {
@@ -54,12 +55,12 @@ func (ss *Snapshot) Simple(ctx context.Context, params *SnapshotParams) error {
 	lastFilter := stream.V(0)
 	// 使用普通帧截图时，必须要传截图间隔，除非只截一张
 	switch params.FrameType {
-	case 0: // 关键帧
+	case 0: // 仅关键帧截图
 		selectFilter := filter.Select("'eq(pict_type,I)'")
 		filters = append(filters, selectFilter)
 		lastFilter = selectFilter
 		outputOptions = append(outputOptions, output.VSync("vfr"))
-	case 1:
+	case 1: // 等间隔截图
 		if params.Num != 1 {
 			if params.IntervalFrames > 0 {
 				selectFilter := filter.Select(fmt.Sprintf("'not(mod(n,%d))'", params.IntervalFrames))
@@ -72,6 +73,17 @@ func (ss *Snapshot) Simple(ctx context.Context, params *SnapshotParams) error {
 				lastFilter = fpsFilter
 			}
 		}
+	case 2: // 指定帧序列截图
+		if len(params.Frames) > 0 {
+			selectExpr := fmt.Sprintf("'%s'",
+				strings.Join(sugar.Map(params.Frames, func(frame int32) string {
+					return fmt.Sprintf("eq(n,%d)", frame)
+				}), "+"))
+			selectFilter := filter.Select(selectExpr)
+			filters = append(filters, selectFilter)
+			lastFilter = selectFilter
+			outputOptions = append(outputOptions, output.VSync("vfr"))
+		}
 	}
 	if params.Width > 0 || params.Height > 0 {
 		scaleFilter := filter.Scale(params.Width, params.Height).Use(lastFilter)
diff --git a/snapshot_params.go b/snapshot_params.go
index d207f4a..2fad771 100644
--- a/snapshot_params.go
+++ b/snapshot_params.go
@@ -1,15 +1,23 @@
 package liv
 
 type SnapshotParams struct {
-	Infile         string
-	Outfile        string
-	StartTime      float32
+	Infile  string
+	Outfile string
+
+	// 0-仅关键帧截图 1-等间隔截图 2-指定帧序列截图
+	FrameType int32 // 截图类型
+
+	// 等间隔截图
 	Interval       int32 // 间隔时间
 	IntervalFrames int32 // 间隔帧数
-	Num            int32
-	FrameType      int32 // 0-仅关键帧 1-指定时间点的帧
-	Width          int32
-	Height         int32
+
+	// 指定帧序列截图
+	Frames []int32 // 帧序列
+
+	StartTime float32 // 截图开始时间。截图类型为指定帧序列截图时不建议使用此参数
+	Num       int32   // 截图最大数量
+	Width     int32
+	Height    int32
 }
 
 type SpriteParams struct {