DIYgod/RSSHub · error · Error

cannot inflate a stripped jpeg

Error message

cannot inflate a stripped jpeg

What it means

ExpandInlineBytes reconstructs a full JPEG from a Telegram 'stripped thumbnail' (the inline thumbnail format described in core.telegram.org/api/files#stripped-thumbnails). It throws when the input buffer is shorter than 3 bytes or its first byte is not 0x01, which is the version marker that the inflation logic expects. Any other byte means the buffer is not a recognized stripped-thumbnail payload.

Source

Thrown at lib/routes/telegram/channel-media.ts:21

import type { TelegramClient } from 'teleproto';
import { Api } from 'teleproto';
import { returnBigInt as bigInt } from 'teleproto/Helpers.js';

import { config } from '@/config';
import InvalidParameterError from '@/errors/types/invalid-parameter';
import type { Route } from '@/types';
import cacheModule from '@/utils/cache/index';

import { getClient, getDocument, getFilename, unwrapMedia } from './tglib/client';

/**
 * https://core.telegram.org/api/files#stripped-thumbnails
 * @param bytes Buffer
 * @returns Buffer jpeg
 */
function ExpandInlineBytes(bytes: Buffer) {
    if (bytes.length < 3 || bytes[0] !== 0x1) {
        throw new Error('cannot inflate a stripped jpeg');
    }
    const header = Buffer.from([
        0xff, 0xd8, 0xff, 0xe0, 0x00, 0x10, 0x4a, 0x46, 0x49, 0x46, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0xff, 0xdb, 0x00, 0x43, 0x00, 0x28, 0x1c, 0x1e, 0x23, 0x1e, 0x19, 0x28, 0x23, 0x21, 0x23, 0x2d, 0x2b,
        0x28, 0x30, 0x3c, 0x64, 0x41, 0x3c, 0x37, 0x37, 0x3c, 0x7b, 0x58, 0x5d, 0x49, 0x64, 0x91, 0x80, 0x99, 0x96, 0x8f, 0x80, 0x8c, 0x8a, 0xa0, 0xb4, 0xe6, 0xc3, 0xa0, 0xaa, 0xda, 0xad, 0x8a, 0x8c, 0xc8, 0xff, 0xcb, 0xda, 0xee,
        0xf5, 0xff, 0xff, 0xff, 0x9b, 0xc1, 0xff, 0xff, 0xff, 0xfa, 0xff, 0xe6, 0xfd, 0xff, 0xf8, 0xff, 0xdb, 0x00, 0x43, 0x01, 0x2b, 0x2d, 0x2d, 0x3c, 0x35, 0x3c, 0x76, 0x41, 0x41, 0x76, 0xf8, 0xa5, 0x8c, 0xa5, 0xf8, 0xf8, 0xf8,
        0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8,
        0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xf8, 0xff, 0xc0, 0x00, 0x11, 0x08, 0x00, 0x00, 0x00, 0x00, 0x03, 0x01, 0x22, 0x00, 0x02, 0x11, 0x01, 0x03, 0x11, 0x01, 0xff, 0xc4, 0x00, 0x1f, 0x00, 0x00, 0x01, 0x05,
        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0xff, 0xc4, 0x00, 0xb5, 0x10, 0x00, 0x02, 0x01, 0x03, 0x03, 0x02, 0x04,
        0x03, 0x05, 0x05, 0x04, 0x04, 0x00, 0x00, 0x01, 0x7d, 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1,
        0x15, 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a,
        0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
        0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
        0xd8, 0xd9, 0xda, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xff, 0xc4, 0x00, 0x1f, 0x01, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
        0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0xff, 0xc4, 0x00, 0xb5, 0x11, 0x00, 0x02, 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05, 0x04, 0x04, 0x00,
        0x01, 0x02, 0x77, 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71, 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62,
        0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57,
        0x58, 0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a,
        0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe2,

View on GitHub (pinned to bed535e087)

Solutions

  1. Guard callers of ExpandInlineBytes so a short/unknown-version buffer skips the thumbnail rather than crashing the whole media stream.
  2. Confirm the teleproto version pinned in package.json matches the stripped-thumbnail encoding the code assumes (first byte 0x01).
  3. If a new stripped-thumbnail version exists, extend ExpandInlineBytes to branch on the version byte and only throw for truly unknown versions.
  4. Log the byte length and first byte when the guard trips to identify corruption vs. version mismatch.

Example fix

// before
function ExpandInlineBytes(bytes: Buffer) {
    if (bytes.length < 3 || bytes[0] !== 0x1) {
        throw new Error('cannot inflate a stripped jpeg');
    }
    ...
}

// after: let the caller decide; return null for unknown versions
function ExpandInlineBytes(bytes: Buffer): Buffer | null {
    if (bytes.length < 3) {
        return null;
    }
    if (bytes[0] !== 0x1) {
        return null; // unknown stripped-thumbnail version
    }
    ...
}
// caller:
const inflated = ExpandInlineBytes(size.bytes);
if (inflated) { yield inflated; } else { yield* streamDocument(client, doc, size.type ?? ''); }
Defensive patterns

Strategy: validation

Validate before calling

function isStrippable(bytes: Buffer): boolean {
    return bytes.length >= 3 && bytes[0] === 0x1;
}
// before calling ExpandInlineBytes:
// if (!isStrippable(size.bytes)) { skip thumbnail }

Type guard

function isStrippedJpegBytes(bytes: unknown): bytes is Buffer {
    return Buffer.isBuffer(bytes) && bytes.length >= 3 && bytes[0] === 0x1;
}

Try / catch

try {
    yield ExpandInlineBytes(size.bytes);
} catch (e) {
    if (e instanceof Error && /cannot inflate a stripped jpeg/.test(e.message)) {
        // fall back to streaming the document's largest thumb or the file itself
        yield* streamDocument(client, doc, size && 'type' in size ? size.type : '');
        return;
    }
    throw e;
}

Prevention

When it happens

Trigger: streamThumbnail passes size.bytes from an Api.PhotoCachedSize/Api.PhotoStrippedSize into ExpandInlineBytes, but the bytes are empty, truncated, or use a newer/unknown stripped-thumbnail version whose marker is not 0x01.

Common situations: A teleproto version change alters how stripped-size bytes are exposed; a corrupt/partial document download yields a short buffer; the channel post references a media type whose thumbnail is a PhotoCachedSize whose bytes do not start with 0x01.

Related errors


AI-assisted analysis of DIYgod/RSSHub@bed535e087 (2026-08-12). Data as JSON: /api/errors/0439ca4f2ae68290. Report an issue: GitHub.