Videos are shrunk on the phone before upload; nostr.build is the first media host.

No public Blossom host transcodes (nostr.build's and primal's BUD-05 /media
return the same bitrate), so a 15-20 Mbps phone clip stalled on playback.
src/video-compress.js re-encodes on the device with WebCodecs via
Mediabunny (a lazily loaded chunk, left out of the SW precache and the
standalone file): H.264, short edge 720, ~2.5 Mbps, moov first, audio
passed through, rotation baked in. Anything short of a clear win uploads
the original. A toast counts the shrinking down.

Media hosts: blossom.nostr.build first, nostr.download second (it was
unreachable for hours); a HEAD probe skips a host that doesn't answer
within 5 s instead of waiting out the whole upload timeout.

video-compress-test: 1080p 20 Mbps 5 s (landscape and rotated portrait) →
1.6 MB H.264 720p 2.49 Mbps with audio, moov first, in 2-3 s.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Du1qT1wbkYwYK6zkGH79Rp

1 files changed, 12 insertions, 5 deletions

diff --git a/src/media-upload.js b/src/media-upload.js
index 686fec5..8e5e8ed 100644
--- a/src/media-upload.js
+++ b/src/media-upload.js
@@ -2,10 +2,11 @@ import { sha256 } from '@noble/hashes/sha256';
 import { bytesToHex } from '@noble/hashes/utils';
 
 // Independent public hosts: a phone upload should not fail just because one
-// provider is down or rejects a particular container. nostr.download's NIP-96
-// document currently advertises large image/video/audio uploads; nostr.build
-// is the second, widely-used Blossom home.
-export const PUBLIC_MEDIA_SERVERS = ['https://nostr.download', 'https://blossom.nostr.build'];
+// provider is down or rejects a particular container. nostr.build is the
+// widely-used Blossom home and goes first; nostr.download (which advertises
+// large image/video/audio uploads) is the fallback — it was unreachable for
+// hours on 2026-09-30, and every upload waited on it.
+export const PUBLIC_MEDIA_SERVERS = ['https://blossom.nostr.build', 'https://nostr.download'];
 
 export class MediaUploadError extends Error {
   constructor(code, details = '') {
@@ -59,7 +60,13 @@ export async function uploadPublicMedia(file, signEvent, {
   if (!auth) throw new MediaUploadError('failed');
   const authorization = 'Nostr ' + btoa(JSON.stringify(auth));
   const failures = [];
-  for (const server of servers) {
+  for (const [i, server] of servers.entries()) {
+    // A host that doesn't answer at all costs a few seconds, not the whole
+    // upload timeout. Any HTTP answer, even an error, means it's there.
+    if (i < servers.length - 1) {
+      try { await fetcher(server.replace(/\/$/, '') + '/upload', { method: 'HEAD', signal: AbortSignal.timeout(5000) }); }
+      catch (error) { failures.push({ status: 0, reason: 'unreachable' }); continue; }
+    }
     try {
       const response = await fetcher(server.replace(/\/$/, '') + '/upload', {
         method: 'PUT', body: file, signal: AbortSignal.timeout(timeoutMs),