Media tools
Sume media tools by API: trim, filter, captions, frames, inspect, speech-to-text, upscaling, background removal, transitions, and Timeline assembly.
Start with Video editing API limits: Sume media tool caps in one table
Crop a 10-minute 16:9 ad to 9:16: filter stops at 300 s, so split
Sume video filter takes sources of 300 seconds or less; TikTok non-Spark ads run to 10 minutes. Two trims, two crops and a timeline cost $1.08. The steps.
Is a 180 second video still a YouTube Short? Trim to 179.5 for margin
YouTube's Shorts page says up to 3 minutes. It says nothing on rounding, so cut to 179.5 s with Sume video trim (duration accepts decimals, $0.02 a job).
TikTok safe zone captions: anchor_ratio and safe_width_ratio on Sume
TikTok's ad page says safe zones vary by orientation and caption length and ships reference files. Sume's caption design fields move the line; ranges listed.
Timeline refuses more than 8 chained fades: countdown cut fix
Sume Timeline 1.0 refuses more than 8 adjacent fades with too_many_chained_transitions. Alternate hard cuts and fades in a 12-clip holiday countdown.
Transparent sticker: GPT Image 2.5 background field or Nano Banana 2.1
Only GPT Image 2.5 lists a background field on Sume. Nano Banana 2.1 does not, so a transparent PNG there is $0.10 plus a $0.0225 background-removal step.
Trim a 4-minute video to a 180 s YouTube Short: start 30, duration 180
YouTube's Shorts page allows up to 3 minutes. Sume video trim cuts 180 seconds from a 240 second source for $0.02. The request, the limits and the refusals.
1:1 clip on a 540x960 TikTok canvas: cover, contain or blur
A 1080x1080 clip on a 540x960 Timeline canvas: contain leaves 210 px bars top and bottom, cover cuts 420 px, blur fills the bars. All cost $0.10 a minute.
Crop 1920x1080 to 9:16: video-filter width 0.3164, x 0.3418
To get a 9:16 strip from a 1920x1080 clip, send a Sume video-filter crop with x 0.3418, y 0, width 0.3164, height 1: about 608x1080, above TikTok's 540x960.
Music bed shorter than the voiceover: loop, fade and duck in Timeline
If a Music 1.0 bed ends before your narration, Sume's Timeline soundtrack can loop it, fade out up to 10 seconds and duck 0 to 20 dB under speech. The settings.
90 s Audio Library song in a 3-minute Short: what covers the rest
YouTube lets a Shorts Audio Library song play up to 90 s in a 3-minute Short. Sume Music 1.0 is $0.125 a track; Timeline loops a bed for $0.30.
Extract the first 90 seconds of a video's audio: audio-detach range
Send audio-detach range {start 0, end 90} for $0.01: 17.28 MB as 48 kHz stereo wav or 1.44 MB as 128 kbps mp3, a Shorts Audio Library song's 90 s.
Keyframe or exact trim for a TikTok ad: which keeps 516 kbps?
Sume video-trim exact re-encodes with libx264; keyframe copies the stream. You cannot set bitrate, so measure size / duration against TikTok's 516 kbps floor.
Crop a 21:9 video to 9:16, 4:5, 1:1 and 16:9: fraction table
From a 21:9 source, a full-height crop is 0.2411 wide for 9:16, 0.3429 for 4:5, 0.4286 for 1:1, 0.7619 for 16:9. $0.02 per crop; the check is free.
Five caption looks on one clip: one transcription, four restyles
Test five caption styles on one video for $1.00: the first job transcribes, four source_caption_id restyles reuse the word timings. Request bodies included.
Brand-color captions: punch and tiktok-green skip design
Sume's docs say punch and tiktok-green read none of the design tokens. To change a caption color per request, use slam or a Hangul style. Token groups.
Timeline output fps: omit it to follow your clips, or get a warning
Leave output.fps out and Timeline 1.0 follows your longest video sources. Force 30 on 24 fps clips and the job warns output_fps_resamples_sources.
A 1.5-second clip allows a 0.75-second fade: Timeline limits
Timeline 1.0 caps a transition at 1 second and 50% of the shorter neighbor clip. Table of the maximum fade for 0.5 to 4 second clips, plus the refusal codes.
Korean captions on a small phone: clip-wipe or black-outline?
Sume lists six Hangul caption styles. The docs call black-outline the safe default and clip-wipe the clearest at small phone sizes. Fonts and the 400 rule.
Music Router negative_prompt: send an empty string, not a list
Sume Music Router takes negative_prompt only omitted or as an empty string. Put exclusions in the prompt. Duration is refused too. Price stays $0.125.
45-minute recording: audio detach fails past 1800 s, what to do
Sume audio detach accepts a source up to 1800 seconds and returns up to 900. A 45-minute video is 2700 s, so trim first. Here is the arithmetic.
STT-ready audio: detach as 16000 Hz mono wav in one call
Sume audio detach can output the STT shape directly: sample_rate 16000 with channels mono, in sample-exact wav, for $0.01 per job.
Sentence segments from video inspect: caption lines with no gaps
Sume video inspect with transcribe true can return gapless sentence segments, with silence_split_seconds from 0.2 to 3. Feed them to captions as cues.
caption_no_speech: why a caption job fails on a silent clip
A Sume caption job returns caption_no_speech when the clip has no audible speech. The fix is cues, segments or words, not a retry.
Change one caption color: design.colors.active and what it accepts
A Sume caption design override changes one token for one request. Colors take hex, rgb(), rgba() or transparent; other CSS is rejected at request time.
Korean caption fonts: 29 Hangul faces and each style's default
Sume video captions list 29 Hangul fonts under the font field. See which face each style uses by default and what the API rejects.
Korean captions on slam return 400: caption_hangul_text_latin_style
Sending Hangul text to slam, punch or tiktok-green returns 400. Sume refuses rather than burn tofu boxes. Use black-outline or a Hangul style.
Lyria prompt section markers: [0:00-0:30] Intro on Sume Music
Sume Music has no duration field. You shape a track with section markers like [0:00-0:30] Intro and a stated length in the prompt itself.
Meta feed sound is optional but recommended: add a ducked music bed
Meta says captions and sound are optional but recommended on Facebook Feed video. Add a music bed under a voice with Sume Timeline soundtrack and duck_db.
Music API duration_seconds rejected: set track length in the prompt
Sume Music 1.0 and the Music Router reject duration and duration_seconds. Put the length in the prompt (a 2-minute track) and use time markers.
Music prompt limit: 5000 characters is plenty for a Lyria brief
The Sume Music prompt takes 1 to 5000 characters. A full seven-axis brief with section markers is far shorter, so the limit rarely binds.
Scoring contrasting scenes: 12 BPM apart and a new lead instrument
Sume's music brief rule for contrasting scenes: change the genre family, move tempo at least 12 BPM, and swap the lead instrument. Keep them for one score.
One TTS job per sentence, then a gapless concat: the Sume recipe
Generate narration one sentence at a time with tts_create, then join the takes with timeline audio. Fix one line without redoing the rest.
Do punch and tiktok-green captions accept design overrides? No
In Sume video captions, punch and tiktok-green do not support design: they render on a path that reads none of the tokens. Use another style to tune.
script_alignment_mismatch: fixing a caption job with script_text
When script_text does not match the speech, a Sume caption job fails with script_alignment_mismatch or script_alignment_failed. Simplify the script or omit it.
Timeline soundtrack duck_db: 0 to 20 dB, needs a real audio spine
Sume Timeline soundtrack.duck_db accepts 0 to 20 and returns duck_requires_audio_spine on silence. Use it with a voiceover spine; gain_db covers a static level.
Timeline audio concat fails on mono plus stereo: channel mismatch
Joining a mono and a stereo file in Sume timeline audio returns audio_parts_channel_mismatch. Detach both as mono, or match layouts first.
Timeline render_strategy_unsafe: why single fails above 12 slots
Timeline returns render_strategy_unsafe when strategy single is used with over 12 slots. Leave it on auto, which chunks past 12 segments. Limits and the fix.
Timeline too_many_chained_transitions: 8 fades, then a hard cut
Sume Timeline allows at most 8 adjacent fades and returns too_many_chained_transitions past that. Each fade is 1 s or less and 50% of the shorter slot. The fix.
wav or mp3 for joined audio: priming padding at every edge
Sume timeline audio outputs wav by default and mp3 as an option. Keep wav if you join again or lip-sync: mp3 adds priming padding at every edge.
Which AI video models make a 20-second clip in one job on Sume?
Seedance 2.5 (4-30 s) and Wan 3.0 (2-30 s) cover 20 seconds in one job on Sume. Omni Flash 1.1 stops at 10 s, MiniMax H3 at 15 s. Full duration table.
Crop 1920x1080 to 9:16 around a left-third subject: x = 0.1751
Video filter crop fractions for an off-center 9:16 strip from a 1920x1080 clip: x 0.1751, width 0.3164, height 1. About $0.02 plus a $0.10 Timeline render.
RMBG costs the same for a 24 MP photo and a 0.5 MP thumbnail
Sume remove-background is $0.0225 per image regardless of size, so resizing before a cutout saves upload time, not money. 600-image arithmetic inside.
Add captions to a Vidu Q4 clip with Sume: what the caption API needs
Vidu Q4 Preview can voice characters. Sume's video captions API burns captions onto any public HTTPS clip; it fails on silent clips unless you send cues.
TikTok 540x960 minimum: a 480p clip needs upscale factor 1.2, not 1.1
A 480-px-wide vertical clip fails TikTok's 540x960 floor. Sume video upscale starts at 1.1, which gives only 528 px. Use 1.2 or more; 25 clips cost $2.70.
Voiceover spine: wav or mp3? 1,800 s is 158.76 MB or 28.8 MB
Timeline audio returns wav (sample-exact) or mp3 (smaller, padding at each edge). 1,800 s is 158.76 MB as 44.1 kHz mono wav vs 28.8 MB at 128 kbps.
What prompt makes a 15-second Black Friday ad track?
Write the track as three timed sections: build, drop, sting. The Music Router takes it for a flat $0.125; the whole 15-second ad is $2.305 on Sume.
One lip-sync model per video: Fabric runs at 25 fps, measure H3 Max
Mixing Fabric and MiniMax H3 Max lip-sync clips in one Sume video risks a frame-rate mismatch. Pick one per run and check fps with ffprobe on the first clip.
Caption a talking-head video: style, placement and phrasing
Caption a talking-head clip with the Sume API: pick a style, move the line off the face, set words per card. One request, $0.20 for up to 60 seconds.