The term "Dual Audio" typically implies a video file (often MKV or MP4) that contains two audio tracks—usually the original English track and a dubbed track (commonly Hindi, Tamil, or Telugu for South Asian release markets).
Why does this matter? If the encoder keeps the video bitrate constant, adding a second audio track doesn’t hurt quality. But often, to keep file sizes “reasonable,” encoders lower the video bitrate for 1080p dual audio releases. A 1080p file at 3.5 GB may have a video bitrate of only 3–4 Mbps — too low for 1080p — causing blockiness in action scenes (like the bullet train fight). Meanwhile, a 720p file at 2 GB can have a higher relative bitrate (3.5–4 Mbps for 720p is excellent). the wolverine 2013 dual audio 720p or 1080p better
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