#9 NTSC: generate_preview error "height not divisible by 4 (720x486)"

[Peter B.]

The command used to generate the preview copy:

/usr/local/bin/ffmpeg-stable -probesize 50M -analyzeduration 50M -i /opt/dva-profession/workflow/final/v-29161/hires/v-29161.mkv -map 0 -map_metadata 0 -pix_fmt yuv420p -c:v libx264 -preset fast -crf 20 -flags +ildct -x264-params keyint=15 -c:a aac -b:a 256k -ar 48000 -ac 2 "/opt/dva-profession/workflow/05-generate_preview/in_progress/v-29161/lowres/v-29161_k01.mp4"

The error message:

[libx264 @ 0x6d2cc40] height not divisible by 4 (720x486)
[vost#0:0/libx264 @ 0x6d2c740] Error while opening encoder - maybe incorrect parameters such as bit_rate, rate, width or height.
Error while filtering: Generic error in an external library
[out#0/mp4 @ 0x6d15080] Nothing was written into output file, because at least one of its streams received no packets.

To be continued...

[Peter B.]

Related info links:
Are we using the correct PAR settings? (vrecord issue #689)

Current vrecord resolutions (2024-05): https://github.com/amiaopensource/vrecord/issues/689#issuecomment-2108177958

https://forum.videohelp.com/threads/405710-Why-does-NTSC-video-usually-get-captured-at-a-resolution-of-720x480

[Peter B.]

Fixed in revision #534.

There's now a new option "FILTERS_CROP[]" in config.inc.php which allows to set crop-conditions in "generate_preview" based on source resolution.