diff --git a/demos/composition/src/main/java/androidx/media3/demo/composition/CompositionPreviewViewModel.kt b/demos/composition/src/main/java/androidx/media3/demo/composition/CompositionPreviewViewModel.kt
index a784c9bf937..446c8e798a8 100644
--- a/demos/composition/src/main/java/androidx/media3/demo/composition/CompositionPreviewViewModel.kt
+++ b/demos/composition/src/main/java/androidx/media3/demo/composition/CompositionPreviewViewModel.kt
@@ -491,13 +491,42 @@ class CompositionPreviewViewModel(application: Application) : AndroidViewModel(a
         return@launch
       }
 
-      val newItem =
-        Media(
-          durationUs = durationUs,
-          title = displayName,
-          uri = uri.toString(),
-          selectedEffects = emptySet(),
+      val uriString = uri.toString()
+      val newItems = mutableListOf<Media>()
+      if (durationUs > SPLIT_THRESHOLD_US) {
+        newItems.add(
+          Media(
+            durationUs = SPLIT_THRESHOLD_US,
+            title = "$displayName (part 1)",
+            uri = uriString,
+            selectedEffects = emptySet(),
+            clipStartUs = 0L,
+            clipEndUs = SPLIT_THRESHOLD_US,
+            originalDurationUs = durationUs,
+          )
+        )
+        newItems.add(
+          Media(
+            durationUs = durationUs - SPLIT_THRESHOLD_US,
+            title = "$displayName (part 2)",
+            uri = uriString,
+            selectedEffects = emptySet(),
+            clipStartUs = SPLIT_THRESHOLD_US,
+            clipEndUs = durationUs,
+            originalDurationUs = durationUs,
+          )
         )
+        Log.i(TAG, "Split media \"$displayName\" at ${SPLIT_THRESHOLD_US / 1_000_000}s into 2 parts")
+      } else {
+        newItems.add(
+          Media(
+            durationUs = durationUs,
+            title = displayName,
+            uri = uriString,
+            selectedEffects = emptySet(),
+          )
+        )
+      }
 
       withContext(Dispatchers.Main) {
         _uiState.update { currentState ->
@@ -505,7 +534,7 @@ class CompositionPreviewViewModel(application: Application) : AndroidViewModel(a
             currentState.mediaState.selectedItemsBySequence.toMutableList()
           if (sequenceIndex < currentItemsBySequence.size) {
             val updatedItems = currentItemsBySequence[sequenceIndex].toMutableList()
-            updatedItems.add(newItem)
+            updatedItems.addAll(newItems)
             currentItemsBySequence[sequenceIndex] = updatedItems
           }
           currentState.copy(
@@ -776,11 +805,19 @@ class CompositionPreviewViewModel(application: Application) : AndroidViewModel(a
             sequenceBuilder.addGap(item.durationUs)
           }
           is Media -> {
-            val mediaItem =
+            val mediaItemBuilder =
               MediaItem.Builder()
                 .setUri(item.uri)
                 .setImageDurationMs(usToMs(item.durationUs)) // Ignored for audio/video
-                .build()
+            if (item.clipStartUs > 0L || item.clipEndUs < Long.MAX_VALUE) {
+              val clippingConfig =
+                MediaItem.ClippingConfiguration.Builder()
+                  .setStartPositionUs(item.clipStartUs)
+                  .setEndPositionUs(item.clipEndUs)
+                  .build()
+              mediaItemBuilder.setClippingConfiguration(clippingConfig)
+            }
+            val mediaItem = mediaItemBuilder.build()
             val effectsForItem = mutableListOf<Effect>()
             for (effectName in item.selectedEffects) {
               // TODO(b/433484977): Order of applied effects should be more clear in the UI
@@ -804,8 +841,9 @@ class CompositionPreviewViewModel(application: Application) : AndroidViewModel(a
                 // Required for image inputs. For video inputs, it sets the target FPS.
                 .setFrameRate(DEFAULT_FRAME_RATE_FPS)
                 // Setting duration explicitly is only required for preview with CompositionPlayer,
-                // and is not needed for export with Transformer.
-                .setDurationUs(item.durationUs)
+                // and is not needed for export with Transformer. When clipping is used, this must
+                // be the original media duration so getClippedDuration can compute correctly.
+                .setDurationUs(item.originalDurationUs)
             sequenceBuilder.addItem(itemBuilder.build())
           }
         }
@@ -1018,6 +1056,7 @@ class CompositionPreviewViewModel(application: Application) : AndroidViewModel(a
     // and provide a stable, readable real-time playback FPS value in the UI.
     private const val FPS_TRACKING_DURATION_MS = 3000L
     private const val DEFAULT_IMAGE_DURATION_US = 1_000_000L
+    private const val SPLIT_THRESHOLD_US = 3_000_000L
     val MEDIA_TYPES = arrayOf("video/*", "image/*", "audio/*")
     val HDR_MODE_DESCRIPTIONS =
       mapOf(
diff --git a/demos/composition/src/main/java/androidx/media3/demo/composition/data/CompositionState.kt b/demos/composition/src/main/java/androidx/media3/demo/composition/data/CompositionState.kt
index 68eccd9749a..02734666d3b 100644
--- a/demos/composition/src/main/java/androidx/media3/demo/composition/data/CompositionState.kt
+++ b/demos/composition/src/main/java/androidx/media3/demo/composition/data/CompositionState.kt
@@ -89,6 +89,9 @@ data class Media(
   val uri: String,
   val selectedEffects: Set<String> = emptySet(),
   val speed: Float = 1.0f,
+  val clipStartUs: Long = 0L,
+  val clipEndUs: Long = Long.MAX_VALUE,
+  val originalDurationUs: Long = durationUs,
 ) : Item {
   override fun copy(): Item =
     copy(
@@ -97,6 +100,9 @@ data class Media(
       uri = uri,
       selectedEffects = selectedEffects,
       speed = speed,
+      clipStartUs = clipStartUs,
+      clipEndUs = clipEndUs,
+      originalDurationUs = originalDurationUs,
     )
 }
 
diff --git a/libraries/effect/src/main/java/androidx/media3/effect/SimpleGlFrameProcessor.kt b/libraries/effect/src/main/java/androidx/media3/effect/SimpleGlFrameProcessor.kt
index df46d63608d..f9d4857fd56 100644
--- a/libraries/effect/src/main/java/androidx/media3/effect/SimpleGlFrameProcessor.kt
+++ b/libraries/effect/src/main/java/androidx/media3/effect/SimpleGlFrameProcessor.kt
@@ -39,6 +39,7 @@ import androidx.media3.common.VideoFrameProcessingException
 import androidx.media3.common.util.ExperimentalApi
 import androidx.media3.common.util.GlProgram
 import androidx.media3.common.util.GlUtil
+import androidx.media3.common.util.Log
 import androidx.media3.common.util.Size
 import androidx.media3.common.util.Util
 import androidx.media3.common.video.AsyncFrame
@@ -115,6 +116,7 @@ private constructor(
   private val overlayMatrixProvider = OverlayMatrixProvider()
   private var targetFormat: Format? = null
   private var presentationEffect: Presentation? = null
+  private var lastItemIndex: Int = -1
 
   private val lock = Any()
   @GuardedBy("lock") private var needsWakeup = false
@@ -226,6 +228,14 @@ private constructor(
       inputReleaseFences = result.readCompleteFences
 
       // Step 4: Update the output frame with the new content time and metadata.
+      val itemIndex = firstInputFrame.metadata[KEY_ITEM_INDEX] as? Int ?: -1
+      if (itemIndex != lastItemIndex) {
+        Log.d(TAG, "Packet changed: itemIndex=$lastItemIndex -> $itemIndex" +
+          " at contentTimeUs=${firstInputFrame.contentTimeUs}")
+        lastItemIndex = itemIndex
+      }
+      Log.d(TAG, "Processing frame: contentTimeUs=${firstInputFrame.contentTimeUs}," +
+        " itemIndex=$itemIndex")
       val updatedOutputFrame =
         (outputFrame.frame as HardwareBufferFrame)
           .buildUpon()
@@ -606,6 +616,8 @@ private constructor(
   }
 
   companion object {
+    private const val TAG = "SimpleGlFrameProcessor"
+    private const val KEY_ITEM_INDEX = "KEY_COMPOSITION_ITEM_INDEX"
     private val FENCE_TIMEOUT = Duration.ofMillis(500)
     private val USAGE = Frame.USAGE_GPU_COLOR_OUTPUT or Frame.USAGE_GPU_SAMPLED_IMAGE
   }