Software: VLC media player (Media)
User query: Please compress the video(named 'project.mp4') into an MPEG-4 file optimized for 1080p TV playback, and save it on the Desktop with an underscore prefix in the name.
Difficulty: hard
Ground-truth plan:
Task 1: Launch VLC and Open the Convert/Save Dialog
Subtask 1: Launch VLC Media Player on your computer.
Subtask 2: Click the 'Media' menu in the upper‑left corner.
Subtask 3: Select 'Convert/Save' to open the Open Media dialog.
Task 2: Add the Source Video
Subtask 1: In the Open Media dialog, click the 'File' tab.
Subtask 2: Click the 'Add…' button in the File Selection section.
Subtask 3: In the file chooser, select the video named 'project.mp4'.
Task 3: Choose the MPEG‑4 (1080p TV/device) Conversion Profile
Subtask 1: Click 'Convert/Save' at the bottom of the Open Media dialog.
Subtask 2: In the Convert window, open the 'Profile' dropdown menu.
Subtask 3: From the list, choose 'Video for MPEG4 1080p TV/device'.
Task 4: Set the Output Filename and Location
Subtask 1: Click 'Browse…' next to the Destination file field.
Subtask 2: Navigate to Desktop.
Subtask 3: Enter a filename with an underscore prefix (e.g., _project.mp4) and click 'Save'.
Task 5: Start the Compression
Subtask 1: Back in the Convert window, click 'Start' to begin compressing the video.
Task 6: Verify the Compressed File
Subtask 1: Navigate to Desktop 
Subtask 2: Confirm '_project.mp4' exists and check its file size to ensure compression was successful.