WIP. adding ken burns operation.

README.md

@@ -136,8 +136,11 @@ Concatenate audio/video assets together into one asset
 ### trim
 Trim audio/video; crop a section of an asset, becomes a new asset
 
+### scale
+Scale a video asset from one size to another
+
 ### overlay
-Overlay one audio or video file onto another
+Overlay one asset onto another
 
 ### ken-burns
 For transforming still images into video via a fade-pan (aka Ken Burns) effect
@@ -171,38 +174,41 @@ Here is a complex example using multiple assets and operations.
       "name": "vid3",
       "path": "https://archive.org/download/gov.archives.arc.49442/gov.archives.arc.49442_512kb.mp4",
       "dest": "src/test/resources/sources/"
+    },
+
+    // Image URL
+    {
+      "name": "img1",
+      "path": "https://live.staticflickr.com/65535/48159911972_01efa0e5ea_b.jpg",
+      "dest": "src/test/resources/sources/"
     }
   ],
   "operations": [
     {
-      "operation": "split",            // name of the operation,
+      "operation": "split",            // name of the operation
       "creates": "vid1_split_%",       // assets it creates, the '%' will be replaced with a counter
-      "split": "vid1",                 // split this source asset
+      "source": "vid1",                // split this source asset
       "interval": "10"                 // split every ten seconds
     },
     {
-      "operation": "concat",           // name of the operation,
+      "operation": "concat",           // name of the operation
       "creates": "recombined_vid1",    // assets it creates, the '%' will be replaced with a counter
-      "concat": ["vid1_split"]         // recombine all split assets
+      "source": ["vid1_split"]         // recombine all split assets
     },
     {
-      "operation": "concat",           // name of the operation,
+      "operation": "concat",           // name of the operation
       "creates": "combined_vid",       // asset it creates, can be referenced later
-      "concat": ["vid1", "vid2"]       // operation-specific: this says, concatenate these named assets
+      "source": ["vid1", "vid2"]       // operation-specific: this says, concatenate these named assets
     },
     {
-      "operation": "concat",           // name of the operation,
+      "operation": "concat",           // name of the operation
       "creates": "combined_vid",       // the asset it creates, can be referenced later
-      "concat": ["vid1", "vid2"]       // operation-specific: this says, concatenate these named assets
+      "source": ["vid1", "vid2"]       // operation-specific: this says, concatenate these named assets
     },
     {
-      "operation": "overlay",          // name of the operation,
-      "creates": {
-        "name": "overlay1",            // asset it creates
-        "width": "1920",               // output width in pixels. default is source width
-        "height": "1024"               // output height in pixes. default is source height
-      },
-      "main": "combined_vid1",         // main video asset
+      "operation": "overlay",          // name of the operation
+      "creates": "overlay1",           // asset it creates
+      "source": "combined_vid1",       // main video asset
       "start": "30",                   // when (on the main video timeline) to begin showing the overlay. default is 0 (beginning)
       "end": "60",                     // when (on the main video timeline) to stop showing the overlay. default is to play the entire overlay
       "overlay": {
@@ -214,6 +220,19 @@ Here is a complex example using multiple assets and operations.
         "x": "source.width / 2",       // horizontal overlay position on main video. default is 0
         "y": "source.height / 2"       // vertical overlay position on main video. default is 0
       }
+    },
+    {
+      "operation": "ken-burns",        // name of the operation
+      "creates": "ken1",               // asset it creates
+      "source": "img1",                // source image
+      "zoom": "1.3",                   // zoom level, from 1 to 10
+      "duration": "5",                 // how long the resulting video will be
+      "start": "0",                    // when to start zooming, default is 0
+      "end": "duration",               // when to end zooming, default is duration
+      "x": "source.width * 0.6",       // pan to this x-position
+      "y": "source.height * 0.4",      // pan to this y-position
+      "width": "1024",                 // width of output video
+      "height": "768"                  // height of output video
     }
   ]
 }

src/main/java/jvcl/main/JvclOptions.java

@@ -48,4 +48,10 @@ public class JvclOptions extends BaseMainOptions {
     @Getter @Setter private File scratchDir = null;
     public File scratchDir() { return scratchDir == null ? new TempDir() : scratchDir; }
 
+    public static final String USAGE_NO_EXEC = "Don't run anything, instead print out commands that would have been run";
+    public static final String OPT_NO_EXEC = "-n";
+    public static final String LONGOPT_NO_EXEC = "--no-exec";
+    @Option(name=OPT_NO_EXEC, aliases=LONGOPT_NO_EXEC, usage=USAGE_NO_EXEC)
+    @Getter @Setter private boolean noExec = false;
+
 }

src/main/java/jvcl/model/JSpec.java

@@ -1,6 +1,6 @@
 package jvcl.model;
 
-import lombok.AllArgsConstructor;
+import jvcl.model.operation.JOperation;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 import lombok.Setter;

src/main/java/jvcl/model/operation/JMultiOperationContext.java

@@ -0,0 +1,18 @@
+package jvcl.model.operation;
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+
+@NoArgsConstructor
+public class JMultiOperationContext extends JOperationContextBase {
+
+    public List<JAsset> sources;
+
+    public JMultiOperationContext(List<JAsset> sources, JAsset output, JFileExtension formatType) {
+        super(output, formatType);
+        this.sources = sources;
+    }
+}

src/main/java/jvcl/model/operation/JMultiSourceOperation.java

@@ -0,0 +1,36 @@
+package jvcl.model.operation;
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import jvcl.service.AssetManager;
+import lombok.Getter;
+import lombok.Setter;
+
+import java.util.List;
+
+import static jvcl.model.JAsset.flattenAssetList;
+import static jvcl.model.JAsset.json2asset;
+import static org.cobbzilla.util.daemon.ZillaRuntime.die;
+import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
+
+public abstract class JMultiSourceOperation extends JOperation {
+
+    @Getter @Setter private String[] sources;
+
+    public JMultiOperationContext getMultiInputContext(AssetManager assetManager) {
+        // validate sources
+        final List<JAsset> sources = flattenAssetList(assetManager.resolve(getSources()));
+        if (empty(sources)) die("operate: no sources");
+
+        // create output object
+        final JAsset output = json2asset(getCreates());
+
+        // if any format settings are missing, use settings from first source
+        output.mergeFormat(sources.get(0).getFormat());
+
+        // set the path, check if output asset already exists
+        final JFileExtension formatType = output.getFormat().getFileExtension();
+
+        return new JMultiOperationContext(sources, output, formatType);
+    }
+}

src/main/java/jvcl/model/JOperation.java → src/main/java/jvcl/model/operation/JOperation.java

@@ -1,7 +1,8 @@
-package jvcl.model;
+package jvcl.model.operation;
 
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.databind.JsonNode;
+import jvcl.model.JAsset;
 import jvcl.operation.exec.ExecBase;
 import lombok.Getter;
 import lombok.NoArgsConstructor;

src/main/java/jvcl/model/operation/JOperationContextBase.java

@@ -0,0 +1,14 @@
+package jvcl.model.operation;
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor @AllArgsConstructor
+public class JOperationContextBase {
+
+    public JAsset output;
+    public JFileExtension formatType;
+
+}

src/main/java/jvcl/model/operation/JSingleOperationContext.java

@@ -0,0 +1,18 @@
+package jvcl.model.operation;
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor @AllArgsConstructor
+public class JSingleOperationContext extends JOperationContextBase {
+    
+    public JAsset source;
+
+    public JSingleOperationContext(JAsset source, JAsset output, JFileExtension formatType) {
+        super(output, formatType);
+        this.source = source;
+    }
+
+}

src/main/java/jvcl/model/operation/JSingleSourceOperation.java

@@ -0,0 +1,24 @@
+package jvcl.model.operation;
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import jvcl.service.AssetManager;
+import lombok.Getter;
+import lombok.Setter;
+
+import static jvcl.model.JAsset.json2asset;
+
+public class JSingleSourceOperation extends JOperation {
+
+    @Getter @Setter private String source;
+
+    public JSingleOperationContext getSingleInputContext(AssetManager assetManager) {
+        final JAsset source = assetManager.resolve(getSource());
+        final JAsset output = json2asset(getCreates());
+        output.mergeFormat(source.getFormat());
+        final JFileExtension formatType = output.getFormat().getFileExtension();
+
+        return new JSingleOperationContext(source, output, formatType);
+    }
+
+}

src/main/java/jvcl/operation/ConcatOperation.java

@@ -1,29 +1,7 @@
 package jvcl.operation;
 
-import jvcl.model.JAsset;
-import jvcl.model.JFileExtension;
-import jvcl.model.JOperation;
-import jvcl.service.AssetManager;
-import jvcl.service.Toolbox;
-import lombok.Getter;
-import lombok.Setter;
+import jvcl.model.operation.JMultiSourceOperation;
 import lombok.extern.slf4j.Slf4j;
 
-import java.io.File;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
-import static jvcl.model.JAsset.flattenAssetList;
-import static jvcl.model.JAsset.json2asset;
-import static org.cobbzilla.util.daemon.ZillaRuntime.die;
-import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
-import static org.cobbzilla.util.io.FileUtil.abs;
-import static org.cobbzilla.util.system.CommandShell.execScript;
-
 @Slf4j
-public class ConcatOperation extends JOperation {
-
-    @Getter @Setter private String[] concat;
-
-}
+public class ConcatOperation extends JMultiSourceOperation {}

src/main/java/jvcl/operation/KenBurnsOperation.java

@@ -0,0 +1,18 @@
+package jvcl.operation;
+
+import jvcl.model.operation.JSingleSourceOperation;
+import lombok.Getter;
+import lombok.Setter;
+
+public class KenBurnsOperation extends JSingleSourceOperation {
+
+    @Getter @Setter private String zoom;
+    @Getter @Setter private String duration;
+    @Getter @Setter private String width;
+    @Getter @Setter private String height;
+    @Getter @Setter private String x;
+    @Getter @Setter private String y;
+    @Getter @Setter private String start;
+    @Getter @Setter private String end;
+
+}

src/main/java/jvcl/operation/OverlayOperation.java

@@ -1,6 +1,6 @@
 package jvcl.operation;
 
-import jvcl.model.JOperation;
+import jvcl.model.operation.JSingleSourceOperation;
 import lombok.Getter;
 import lombok.Setter;
 import lombok.extern.slf4j.Slf4j;
@@ -16,9 +16,8 @@ import static org.cobbzilla.util.daemon.ZillaRuntime.big;
 import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
 
 @Slf4j
-public class OverlayOperation extends JOperation {
+public class OverlayOperation extends JSingleSourceOperation {
 
-    @Getter @Setter private String source;
     @Getter @Setter private OverlayConfig overlay;
 
     @Getter @Setter private String start;

src/main/java/jvcl/operation/SplitOperation.java

@@ -1,7 +1,7 @@
 package jvcl.operation;
 
 import jvcl.model.JAsset;
-import jvcl.model.JOperation;
+import jvcl.model.operation.JSingleSourceOperation;
 import lombok.Getter;
 import lombok.Setter;
 import lombok.extern.slf4j.Slf4j;
@@ -12,9 +12,7 @@ import static jvcl.service.Toolbox.getDuration;
 import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
 
 @Slf4j
-public class SplitOperation extends JOperation {
-
-    @Getter @Setter private String split;
+public class SplitOperation extends JSingleSourceOperation {
 
     @Getter @Setter private String interval;
     public BigDecimal getIntervalIncr() { return getDuration(interval); }

src/main/java/jvcl/operation/TrimOperation.java

@@ -1,30 +1,17 @@
 package jvcl.operation;
 
-import jvcl.model.JAsset;
-import jvcl.model.JFileExtension;
-import jvcl.model.JOperation;
-import jvcl.service.AssetManager;
-import jvcl.service.Toolbox;
+import jvcl.model.operation.JSingleSourceOperation;
 import lombok.Getter;
 import lombok.Setter;
 import lombok.extern.slf4j.Slf4j;
 
-import java.io.File;
 import java.math.BigDecimal;
-import java.util.HashMap;
-import java.util.Map;
 
-import static jvcl.model.JAsset.json2asset;
 import static jvcl.service.Toolbox.getDuration;
-import static org.cobbzilla.util.daemon.ZillaRuntime.die;
 import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
-import static org.cobbzilla.util.io.FileUtil.*;
-import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
-public class TrimOperation extends JOperation {
-
-    @Getter @Setter private String trim;
+public class TrimOperation extends JSingleSourceOperation {
 
     @Getter @Setter private String start;
     public BigDecimal getStartTime() { return empty(start) ? BigDecimal.ZERO : getDuration(start); }
@@ -34,6 +21,6 @@ public class TrimOperation extends JOperation {
     public BigDecimal getEndTime() { return getDuration(end); }
 
     public String shortString() { return "trim_"+getStart()+(hasEnd() ? "_"+getEnd() : ""); }
-    public String toString() { return trim+"_"+getStart()+(hasEnd() ? "_"+getEnd() : ""); }
+    public String toString() { return getSource()+"_"+getStart()+(hasEnd() ? "_"+getEnd() : ""); }
 
 }

src/main/java/jvcl/operation/exec/ConcatExec.java

@@ -2,6 +2,7 @@ package jvcl.operation.exec;
 
 import jvcl.model.JAsset;
 import jvcl.model.JFileExtension;
+import jvcl.model.operation.JMultiOperationContext;
 import jvcl.operation.ConcatOperation;
 import jvcl.service.AssetManager;
 import jvcl.service.Toolbox;
@@ -12,22 +13,12 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-import static jvcl.model.JAsset.flattenAssetList;
-import static jvcl.model.JAsset.json2asset;
-import static org.cobbzilla.util.daemon.ZillaRuntime.die;
-import static org.cobbzilla.util.daemon.ZillaRuntime.empty;
 import static org.cobbzilla.util.io.FileUtil.abs;
 import static org.cobbzilla.util.system.CommandShell.execScript;
 
 @Slf4j
 public class ConcatExec extends ExecBase<ConcatOperation> {
 
-    public static final String CONCAT_RECODE_TEMPLATE_OLD
-            // concat inputs
-            = "{{ffmpeg}} -f concat{{#each sources}} -i {{{this.path}}}{{/each}} "
-            // safely with copy codec
-            + "-safe 0 -c copy {{{output.path}}}";
-
     public static final String CONCAT_RECODE_TEMPLATE_1
             // list inputs
             = "{{ffmpeg}} {{#each sources}} -i {{{this.path}}}{{/each}} "
@@ -39,22 +30,15 @@ public class ConcatExec extends ExecBase<ConcatOperation> {
             + "concat=n={{sources.length}}:v=1:a=1 [v] [a]\" "
 
             // output combined result
-            + "-map \"[v]\" -map \"[a]\" {{{output.path}}}";
+            + "-map \"[v]\" -map \"[a]\" -y {{{output.path}}}";
 
     @Override public void operate(ConcatOperation op, Toolbox toolbox, AssetManager assetManager) {
 
-        // validate sources
-        final List<JAsset> sources = flattenAssetList(assetManager.resolve(op.getConcat()));
-        if (empty(sources)) die("operate: no sources");
-
-        // create output object
-        final JAsset output = json2asset(op.getCreates());
-
-        // if any format settings are missing, use settings from first source
-        output.mergeFormat(sources.get(0).getFormat());
+        final JMultiOperationContext opCtx = op.getMultiInputContext(assetManager);
+        final List<JAsset> sources = opCtx.sources;
+        final JAsset output = opCtx.output;
+        final JFileExtension formatType = opCtx.formatType;
 
-        // set the path, check if output asset already exists
-        final JFileExtension formatType = output.getFormat().getFileExtension();
         final File defaultOutfile = assetManager.assetPath(op, sources, formatType);
         final File path = resolveOutputPath(output, defaultOutfile);
         if (path == null) return;

src/main/java/jvcl/operation/exec/ExecBase.java

@@ -1,7 +1,7 @@
 package jvcl.operation.exec;
 
 import jvcl.model.JAsset;
-import jvcl.model.JOperation;
+import jvcl.model.operation.JOperation;
 import jvcl.service.AssetManager;
 import jvcl.service.Toolbox;
 import lombok.extern.slf4j.Slf4j;

src/main/java/jvcl/operation/exec/KenBurnsExec.java

@@ -0,0 +1,36 @@
+package jvcl.operation.exec;
+
+
+import jvcl.model.JAsset;
+import jvcl.model.JFileExtension;
+import jvcl.model.operation.JSingleOperationContext;
+import jvcl.operation.KenBurnsOperation;
+import jvcl.service.AssetManager;
+import jvcl.service.Toolbox;
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public class KenBurnsExec extends ExecBase<KenBurnsOperation> {
+
+    public static final String KEN_BURNS_TEMPLATE
+            = "{{{ffmpeg}}} -i {{{source.path}}} -filter_complex \""
+            + "scale={{expr width '*' 16}}x{{expr height '*' 16}}, "
+            + "zoompan="
+            + "z='min(zoom*{{zoomIncrementFactor}},{{zoom}})':"
+            + "d={{duration}}:"
+            + "x='if(gte(zoom,{{zoom}}),x,x+{{deltaX}}/a)':"
+            + "y='if(gte(zoom,{{zoom}}),y,y+{{deltaY}})':"
+            + "s={{width}}x{{height}}"
+            + "\" -y {{{output.path}}}";
+
+    @Override public void operate(KenBurnsOperation op, Toolbox toolbox, AssetManager assetManager) {
+
+        final JSingleOperationContext opCtx = op.getSingleInputContext(assetManager);
+        final JAsset source = opCtx.source;
+        final JAsset output = opCtx.output;
+        final JFileExtension formatType = opCtx.formatType;
+
+
+    }
+
+}

src/main/java/jvcl/operation/exec/OverlayExec.java

@@ -2,6 +2,7 @@ package jvcl.operation.exec;
 
 import jvcl.model.JAsset;
 import jvcl.model.JFileExtension;
+import jvcl.model.operation.JSingleOperationContext;
 import jvcl.operation.OverlayOperation;
 import jvcl.service.AssetManager;
 import jvcl.service.Toolbox;
@@ -14,7 +15,6 @@ import java.util.HashMap;
 import java.util.Map;
 
 import static java.math.RoundingMode.HALF_EVEN;
-import static jvcl.model.JAsset.json2asset;
 import static org.cobbzilla.util.daemon.ZillaRuntime.big;
 import static org.cobbzilla.util.io.FileUtil.abs;
 import static org.cobbzilla.util.system.CommandShell.execScript;
@@ -26,17 +26,17 @@ public class OverlayExec extends ExecBase<OverlayOperation> {
             = "ffmpeg -i {{{source.path}}} -i {{{overlay.path}}} -filter_complex \""
             + "[1:v] setpts=PTS-STARTPTS+(1/TB){{#exists width}}, scale={{width}}x{{height}}{{/exists}} [1v]; "
             + "[0:v][1v] overlay={{{overlayFilterConfig}}} "
-            + "\" {{{output.path}}}";
+            + "\" -y {{{output.path}}}";
 
     @Override public void operate(OverlayOperation op, Toolbox toolbox, AssetManager assetManager) {
-        final JAsset source = assetManager.resolve(op.getSource());
-        final OverlayOperation.OverlayConfig overlay = op.getOverlay();
-        final JAsset overlaySource = assetManager.resolve(overlay.getSource());
 
-        final JAsset output = json2asset(op.getCreates());
-        output.mergeFormat(source.getFormat());
+        final JSingleOperationContext opCtx = op.getSingleInputContext(assetManager);
+        final JAsset source = opCtx.source;
+        final JAsset output = opCtx.output;
+        final JFileExtension formatType = opCtx.formatType;
 
-        final JFileExtension formatType = output.getFormat().getFileExtension();
+        final OverlayOperation.OverlayConfig overlay = op.getOverlay();
+        final JAsset overlaySource = assetManager.resolve(overlay.getSource());
 
         final File defaultOutfile = assetManager.assetPath(op, source, formatType);
         final File path = resolveOutputPath(output, defaultOutfile);

src/main/java/jvcl/operation/exec/SplitExec.java

@@ -2,6 +2,7 @@ package jvcl.operation.exec;
 
 import jvcl.model.JAsset;
 import jvcl.model.JFileExtension;
+import jvcl.model.operation.JSingleOperationContext;
 import jvcl.operation.SplitOperation;
 import jvcl.service.AssetManager;
 import jvcl.service.Toolbox;
@@ -12,7 +13,6 @@ import java.math.BigDecimal;
 import java.util.HashMap;
 import java.util.Map;
 
-import static jvcl.model.JAsset.json2asset;
 import static org.cobbzilla.util.daemon.ZillaRuntime.die;
 import static org.cobbzilla.util.io.FileUtil.abs;
 import static org.cobbzilla.util.io.FileUtil.mkdirOrDie;
@@ -22,21 +22,14 @@ import static org.cobbzilla.util.system.CommandShell.execScript;
 public class SplitExec extends ExecBase<SplitOperation> {
 
     public static final String SPLIT_TEMPLATE
-            = "{{ffmpeg}} -i {{{source.path}}} -ss {{startSeconds}} -t {{interval}} {{{output.path}}}";
+            = "{{ffmpeg}} -i {{{source.path}}} -ss {{startSeconds}} -t {{interval}} -y {{{output.path}}}";
 
     @Override public void operate(SplitOperation op, Toolbox toolbox, AssetManager assetManager) {
 
-        final JAsset source = assetManager.resolve(op.getSplit());
-
-        // create output object
-        final JAsset output = json2asset(op.getCreates());
-
-        // if any format settings are missing, use settings from source
-        output.mergeFormat(source.getFormat());
-        assetManager.addOperationArrayAsset(output);
-
-        // get format type
-        final JFileExtension formatType = output.getFormat().getFileExtension();
+        final JSingleOperationContext opCtx = op.getSingleInputContext(assetManager);
+        final JAsset source = opCtx.source;
+        final JAsset output = opCtx.output;
+        final JFileExtension formatType = opCtx.formatType;
 
         final Map<String, Object> ctx = new HashMap<>();
         ctx.put("ffmpeg", toolbox.getFfmpeg());

src/main/java/jvcl/operation/exec/TrimExec.java

@@ -2,6 +2,7 @@ package jvcl.operation.exec;
 
 import jvcl.model.JAsset;
 import jvcl.model.JFileExtension;
+import jvcl.model.operation.JSingleOperationContext;
 import jvcl.operation.TrimOperation;
 import jvcl.service.AssetManager;
 import jvcl.service.Toolbox;
@@ -12,7 +13,6 @@ import java.math.BigDecimal;
 import java.util.HashMap;
 import java.util.Map;
 
-import static jvcl.model.JAsset.json2asset;
 import static org.cobbzilla.util.daemon.ZillaRuntime.die;
 import static org.cobbzilla.util.io.FileUtil.*;
 import static org.cobbzilla.util.system.CommandShell.execScript;
@@ -21,16 +21,17 @@ import static org.cobbzilla.util.system.CommandShell.execScript;
 public class TrimExec extends ExecBase<TrimOperation> {
 
     public static final String TRIM_TEMPLATE
-            = "{{ffmpeg}} -i {{{source.path}}} -ss {{startSeconds}} {{#exists interval}}-t {{interval}} {{/exists}}{{{output.path}}}";
+            = "{{ffmpeg}} -i {{{source.path}}} " +
+            "-ss {{startSeconds}} " +
+            "{{#exists interval}}-t {{interval}} {{/exists}}" +
+            "-y {{{output.path}}}";
 
     @Override public void operate(TrimOperation op, Toolbox toolbox, AssetManager assetManager) {
 
-        final JAsset source = assetManager.resolve(op.getTrim());
-
-        final JAsset output = json2asset(op.getCreates());
-        output.mergeFormat(source.getFormat());
-
-        final JFileExtension formatType = output.getFormat().getFileExtension();
+        final JSingleOperationContext opCtx = op.getSingleInputContext(assetManager);
+        final JAsset source = opCtx.source;
+        final JAsset output = opCtx.output;
+        final JFileExtension formatType = opCtx.formatType;
 
         if (source.hasList()) {
             if (output.hasDest()) {

src/main/java/jvcl/service/AssetManager.java

@@ -2,7 +2,7 @@ package jvcl.service;
 
 import jvcl.model.JAsset;
 import jvcl.model.JFileExtension;
-import jvcl.model.JOperation;
+import jvcl.model.operation.JOperation;
 import org.cobbzilla.util.handlebars.HandlebarsUtil;
 
 import java.io.File;

src/main/java/jvcl/service/OperationEngine.java

@@ -1,6 +1,6 @@
 package jvcl.service;
 
-import jvcl.model.JOperation;
+import jvcl.model.operation.JOperation;
 
 public class OperationEngine {
 

src/main/java/jvcl/service/json/JOperationFactory.java

@@ -4,7 +4,7 @@ import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.deser.DeserializationProblemHandler;
 import com.fasterxml.jackson.databind.jsontype.TypeIdResolver;
-import jvcl.model.JOperation;
+import jvcl.model.operation.JOperation;
 import jvcl.operation.exec.ExecBase;
 
 import java.io.IOException;

src/test/resources/tests/test_concat.jvcl

@@ -9,7 +9,7 @@
         "name": "combined_vid",
         "dest": "src/test/resources/outputs/combined.mp4"
       },
-      "concat": ["vid1_splits[1..]"]
+      "sources": ["vid1_splits[1..]"]
     }
   ]
 }

src/test/resources/tests/test_ken_burns.jvcl

@@ -0,0 +1,24 @@
+{
+  "assets": [
+    {
+      "name": "img1",
+      "path": "https://live.staticflickr.com/65535/48159911972_01efa0e5ea_b.jpg",
+      "dest": "src/test/resources/sources/"
+    }
+  ],
+  "operations": [
+    {
+      "operation": "ken-burns",        // name of the operation
+      "creates": "ken1",               // asset it creates
+      "source": "img1",                // source image
+      "zoom": "1.3",                   // zoom level, from 1 to 10
+      "duration": "5",                 // how long the resulting video will be
+      "start": "0",                    // when to start zooming, default is 0
+      "end": "duration",               // when to end zooming, default is duration
+      "x": "source.width * 0.6",       // pan to this x-position
+      "y": "source.height * 0.4",      // pan to this y-position
+      "width": "1024",                 // width of output video
+      "height": "768"                  // height of output video
+    }
+  ]
+}

src/test/resources/tests/test_split.jvcl

@@ -18,8 +18,8 @@
         "name": "vid1_splits",
         "dest": "src/test/resources/outputs/"
       },
-      "split": "vid1",               // split this source asset
-      "interval": "10",             // split every ten seconds
+      "source": "vid1",              // split this source asset
+      "interval": "10",              // split every ten seconds
       "start": "65",                 // start one minute and five seconds into the video
       "end": "100"                   // end 100 seconds into the video
     }

src/test/resources/tests/test_trim.jvcl

@@ -9,7 +9,7 @@
         "name": "vid1_trims",
         "dest": "src/test/resources/outputs/trims/"
       },
-      "trim": "vid1_splits",         // trim these source assets
+      "source": "vid1_splits",       // trim these source assets
       "start": "1",                  // cropped region starts here, default is zero
       "end": "6"                     // cropped region ends here, default is end of video
     }