Free encoders & image issues Tony Di Bartolo • Media Production Center VMG 20100928 Handbrake • http://handbrake.fr/details.php • Supported Sources: • Any DVD-like source: VIDEO_TS folder, DVD image or real DVD, and some .VOB and .TS files • Most any multimedia file it can get libavformat to read and libavcodec to decode. • Outputs: • File format: MP4 and MKV • Video: MPEG-4, H.264, or Theora • Audio: AAC, CoreAudio AAC (OS X Only), MP3, or Vorbis. AC-3 pass-through, DTS pass-thorugh (MKV only) • Misc features: • Chapter selection, Subtitles • Integrated bitrate calculator • Picture deinterlacing, cropping and scaling • Live Video Preview MPEG Streamclip • http://www.squared5.com/svideo/mpeg-streamclip-mac.html MPEG Streamclip is a powerful high-quality video converter, player, editor for MPEG, QuickTime, transport streams, iPod. And now it is a DivX editor and encoding machine, and even a stream and YouTube downloader. You can use MPEG Streamclip to: open most movie formats including MPEG files or transport streams; play them at full screen; edit them with Cut, Copy, Paste, and Trim; set In/Out points and convert them into muxed or demuxed files, or export them to QuickTime, AVI, DV and MPEG-4 files with more than professional quality, so you can easily import them in Final Cut Pro, DVD Studio Pro, Toast 6, 7, 8, and use them with many other applications or devices. Supported input formats: MPEG, VOB, PS, M2P, MOD, VRO, DAT, MOV, DV, AVI, MP4, TS, M2T, MMV, REC, VID, AUD, AVR, VDR, PVR, TP0, TOD, M2V, M1V, MPV, AIFF, M1A, MP2, MPA, AC3, ... Common encode issues that effect image quality (other than file size & data rate-related issues) • incorrect aspect ratio (squeezed or stretched image, also unnecessary letterbox or pillars) • interlacing artifacts (jagged lines when viewing interlaced material on progressive scan monitors) • frame-rate mismatch (jerky motion, dropped or repeated frames) incorrect aspect ratio? you bet! SD video standards: NTSC • 525 line system, 486 (480) active lines • aspect ratio depends on pixel shape, often 4:3 • 29.97 fps • interlaced - two fields per frame • 59.94 Hz scan rate HD video standards • Two “resolutions”: 1080 or 720 • aspect ratio 16 x 9 • multiple frame rates • interlaced or progressive HD format expression examples: 720p30 • 720 scan lines • progressive scan • 29.97 frames per second 1080i60 • 1080 scan lines • interlaced scan • 59.94 fields per second 1080p, 720p • 1920 x 1080; 1280 x 720 frame size • 16 x 9 aspect ratio • 23.98 (24), 29.97(30) fps frame rates 1080i • 1920 x 1080 frame size • 16 x 9 aspect ratio • 29.97 (30) fps frame rate • 59.94 (60) fields per second A leading contributor to aspect ratio confusion • Most images are recorded anamorphic (squeezed) in order to lower bandwidth • result is non-square pixels • playback device should decode...but double check dimensions in QT movie inspector Be vigilant to make sure your aspect ratio is correct! • when working with anamorphic video in FCP, video is compressed but displays un-squeezed • FCP should correct pixel aspect if sequence settings are correct, but double check these and also your export settings in FCP/Compressor to avoid surprises later • for more info: • http://documentation.apple.com/en/finalcutpro/usermanual/ index.html#chapter=F%26section=8%26tasks=true • http://support.apple.com/kb/TA26788?viewlocale=en_US Interlaced footage with lots of motion can display poorly on progressive displays Interlacing Info • playing interlaced footage on a progressive display can result in flickering, jagged lines • use de-interlace/decombing options when encoding for web • Note field dominance settings: NTSC video - lower fields are displayed first • HD video - upper fields are displayed first.