choppy video, pixelated

[psmankikar]

i'm converting .mov Quicktime files to .flv.
no matter how high i make the bitrate, the resulting file is 1.2MB and EXTREMELY choppy and pixelated.
the original is 31.1 MB. it's only 33 seconds.

[Baldrick]

You could try convert to mp4 with h264 video instead as it's also supported by flash.

[greymalkin]

no matter how high i make the bitrate, the resulting file is 1.2MB

something is wrong with the application you are using or the settings you are using as if you truly were setting the bitrate higher the file would not stay the same size as they are directly related. Are you using variable bitrate? If so try constant.

[Case]

i'm converting .mov Quicktime files to .flv.
no matter how high i make the bitrate, the resulting file is 1.2MB

No short answer here, sorry.
A constant bitrate is used by varying the quantizer values between Qmin and Qmax. Default values for FLV encodes with ffmpegX are Qmin=2 and Qmax=15. (See Options tab.) In general, lower quantizer values get higher quality output and higher quantizer values get lower quality output.

From the ffmpegX website:

Sets the minimum quantizer. The quantizer is the compression level used to encode a frame. More compression means smaller filesize and less image quality. Complex frames will require more compression in order to fit in a constant bitrate, so the quantizer will vary within the qmin/qmax range in attempt to control the bitrate. Range is 1-31, though qmin=1 is not recommended. Setting qmin=qmax will lead to variable bitrate encoding.

Sets the maximum quantizer. Range is 1-31, recommended range is 10-31.

When you set the target video bitrate too high, every frame will be encoded at quantizer value Qmin. This will result in some output bitrate that may be lower than what you had set as target bitrate. ffmpeg just doesn't know what to use the remaining bytes for. It will not use it for extra quality, as it is already encoding at maximum quality (fixed at Qmin).

and EXTREMELY choppy

Did you have to use "Invert mapping" to get this clip to encode? That would be a known issue.

and pixelated.

Did you upscale on playback, or play at the FLV's native resolution? Did you change the target video size (width and height in pixels) from the FLV preset (320x240)?