Audio analysis (Web)

Use ffprobe and ffmpeg via execa to inspect audio streams and downloaded files during a flow. Both tools are pre-installed on QA Wolf runners. See the ffprobe documentation and ffmpeg documentation for the full list of available flags.

Examples

Inspect a stream URL

const { execa } = await import("execa");

const streamUrl = await page.locator("audio").getAttribute("src");

const { stdout } = await execa("ffprobe", [
  "-v", "quiet",
  "-print_format", "json",
  "-show_format",
  "-show_streams",
  "-i", streamUrl,
]);

const metadata = JSON.parse(stdout);
const audioStream = metadata.streams.find((s) => s.codec_type === "audio");

expect(audioStream.codec_name).toBe("aac");
expect(parseInt(metadata.format.bit_rate) / 1000).toBeGreaterThan(100);

Detect silence in a downloaded file

const { execa } = await import("execa");

const { stderr } = await execa("ffmpeg", [
  "-i", filePath,
  "-af", "silencedetect=n=-50dB:d=1",
  "-f", "null", "-",
]);

if (stderr.includes("silence_start")) {
  throw new Error("Audio file contains silence.");
}

Assert file metadata

const { execa } = await import("execa");

const { stdout } = await execa("ffprobe", [
  "-v", "error",
  "-show_entries", "format=bit_rate,duration",
  "-show_streams",
  "-of", "json",
  filePath,
]);

const metadata = JSON.parse(stdout);
const audioStream = metadata.streams.find((s) => s.codec_type === "audio");

expect(audioStream.codec_name).toBe("aac");
expect(parseInt(metadata.format.bit_rate) / 1000).toBeGreaterThan(100);

When to use

Your app streams audio and you need to assert on codec, bitrate, or sample rate.
Your app generates or downloads audio files and you need to verify they aren’t silent or corrupted.
Your app plays back recordings and you need to confirm the file contains valid audio data.
Your test needs to validate audio properties that can’t be asserted through the UI.

Full sample test

import { flow, launch } from "@qawolf/flows/web";

export default flow(
  "Validate audio stream",
  "Web - Chrome",
  async ({ page, test }) => {
    await test("navigate to player and assert stream metadata", async () => {
      // Arrange
      await page.goto("https://your-app.com/player");
      await page.locator("audio").waitFor({ state: "attached" });

      // Act
      const { execa } = await import("execa");
      const streamUrl = await page.locator("audio").getAttribute("src");

      const { stdout } = await execa("ffprobe", [
        "-v", "quiet",
        "-print_format", "json",
        "-show_format",
        "-show_streams",
        "-i", streamUrl,
      ]);

      // Assert
      const metadata = JSON.parse(stdout);
      const audioStream = metadata.streams.find((s) => s.codec_type === "audio");

      expect(audioStream).toBeTruthy();
      expect(audioStream.codec_name).toBe("aac");
      expect(parseInt(metadata.format.bit_rate) / 1000).toBeGreaterThan(100);
    });
  },
);

Email & SMS

Authentication

Networking

Data sharing

Audio

Camera

Accessibility

Performance

Visual diffing

AI & LLMs

Desktop

Sensors

Examples

When to use

Full sample test

​Examples

​When to use

​Full sample test

Examples

When to use

Full sample test