Hi everyone, (hoping you can help demystify a few video questions below)
We've used a small amount of video in our past Articulate projects, relying on FLV and some YouTube embeds.
We're working on a new project that requires multiple video clips and I keep reading on the forums about the use of MP4 h.264 encoded videos over FLV.
We exported videos out of Vegas Video, then converted them to FLV. We uploaded them to a test server and the playback was surprisingly fast, no delay before starting to play. Hurray! You go, FLV!
Curious, we exported MP4 versions straight out of Vegas Video. The MP4 file sizes were a bit smaller than the FLVs, but the playback was nowhere near as good. There's a long delay before playback begins, to the point where you doubt the video will ever start.
Debating whether we should just stick with FLV or are we doing something wrong with these MP4s? Would a pre-loader be the answer? Or stick with FLV and a pre-loader for even more assurance?
Is it accurate to say that FLVs basically stream via a progressive download, and MP4s must download in their entirety before playback begins?
What video format have you had the most success with, and what settings do you use when preparing the files for Articulate integration? Thank you!
I'm going to include the file info from Format Factory for both the FLV and MP4:
(One thing I'm noticing is the frame rate difference below, and the audio bit rate...)
General
Format : Flash Video
File size : 10.3 MiB
Duration : 1mn 44s
Overall bit rate : 828 Kbps
Encoded date : Wed Jun 29 16:42:04 2011
Tagged date : UTC 1970-01-16 03:43:03
Tagging application : Turbine Video Engine SDK
Video
Format : H.263
Codec ID : 2
Codec ID/Hint : Sorenson
Duration : 1mn 44s
Bit rate : 768 Kbps
Width : 427 pixels
Height : 240 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 29.970 fps
Bit depth : 8 bits
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.250
Stream size : 9.61 MiB (94%)
Audio
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 3
Codec ID : 2
Codec ID/Hint : MP3
Duration : 1mn 44s
Bit rate mode : Constant
Bit rate : 48.0 Kbps
Channel(s) : 1 channel
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 672 KiB (6%)
------------------ MP4 Details --------------
General
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 10.0 MiB
Duration : 1mn 43s
Overall bit rate : 887 Kbps
Video
ID : 2
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L2.1
Format settings, CABAC : Yes
Format settings, ReFrames : 5 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 1mn 43s
Bit rate mode : Constant
Bit rate : 768 Kbps
Width : 428 pixels
Height : 240 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 59.940 fps
Original frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.125
Stream size : 9.33 MiB (85%)
Language : English
Encoded date : UTC 2011-07-10 23:45:22
Tagged date : UTC 2011-07-10 23:45:22
Audio
ID : 1
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 1mn 43s
Bit rate mode : Constant
Bit rate : 128 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 1.58 MiB (14%)
Language : English