Delivery requirements for online features
NOTE: This document relates to this commisioning brief and is subject to regular revision and refinement. It is not yet supposed to be a complete list of requirements.
Sections: images | slideshows | video | audio.
Images
These guidelines are based on – and in the spirit of – the BBC's GEL guidelines.
Unless otherwise appropriate, all images SHOULD be 16:9, varying in width by increments of 32px. Here are some examples we've used already:-
- 976x549 (full page width, used in audio slideshows so far);
- 640x360 (full main column width);
- 352x198 (a 9:16 picture and a 1:1 picture adjacent, as per How astronomy in Scotland helps us understand the birth of galaxies;
- 288x162 (best fit for half main column width);
- 176x99 (best fit for a third of main column width).
Images at ratios 32:9, 9:16 or 1:1 MAY occasionally qualify as appropriate variants.
Photographs SHOULD almost always be JPEGs, rarely needing saved at a higher quality setting than 51 in Photoshop. GIFs and PNGs are also allowed where appropriate.
All images MUST include a descriptive ALT attribute and, usually, a caption. The original untouched images would be enormously handy for promotional purposes, too.
At present, the template isn't capable of supporting galleries. There is, however, quite a bit of flexibility over presentation with what we've got. Images at smaller sizes can be aligned so text can flow around them.
More details available at BBC Standards & Guidelines for Design & Editorial.
Audio slideshows
Our slideshows are created with the Soundslides (soundslides.com) application. In its default position as the dominant feature on a page, a slideshow's image size MUST be 976px x 549px. Other shapes and sizes are occasionally editorially justifiable, but MUST be agreed in advance with the commissioner.
The specific deliverables, based on the exported output from a purchased (i.e. not demo) Soundslides tool, are as follows:-
- The folder of images (custom/);
- The audio file (audio_hi.mp3);
- The text file (soundslide.txt);
- The XML file (soundlide.xml).
Note that although Soundslides produces many more files, those above are all we require.
Video (MPEG-4)
Container format: .mp4 or .mov (QuickTime H.264)
Video
- Bit rate / Quality: 5Mbps CBR minimum
- Codec: H.264 / QuickTime
- Frame size: 1024x576 (or smaller, so long as the aspect ratio is preserved)
- Frames per second: 25 (progressive scan)
Audio
- Codec: AAC
- Channels: Stereo
- Bit rate: 192 kbps
- Sample rate: 48 KHz
- Sample depth: 16 bit
We do accept other video formats, so if delivering to this standard is a problem, get in touch.
Irrespective of the video requirements above, our videos are presented at a size of 640px x 360px so shooting at a ratio of 16:9 is almost always a MUST. The obvious exception to that is very old archive footage, which MAY be delivered at 4:3. Video MUST NOT contain black bars at the top and bottom; a widescreen image SHOULD be squeezed anamorphically to fit the frame size above.
A high quality, large image MUST be delivered with each video to display on the page before the video plays.
Audio
- Format: WAV or MP3 (MPEG-1 layer 3)
- Frequency: 44100Hz
- Bitrate: 192kbps
And in STEREO, please, unless the source material is only available in MONO.
