AV2 规范正式落地：下一代视频压缩的实战起点

ffmpeg -encoders 2>/dev/null | grep av1

#!/usr/bin/env bash
# av1_baseline.sh — AV1 编码基准，后续可替换为 AV2 对比
set -euo pipefail

SOURCE="${1:?用法: ./av1_baseline.sh source.mp4}"
OUTPUT_DIR="av1_baseline_results"
mkdir -p "$OUTPUT_DIR"

# 测试码率档位（bps）
RATES=(1000000 2000000 4000000 6000000)

for RATE in "${RATES[@]}"; do
    OUT="${OUTPUT_DIR}/av1_${RATE}.mp4"
    echo "=== 编码码率 ${RATE} bps ==="

    ffmpeg -y -i "$SOURCE" \
        -c:v libaom-av1 \
        -b:v "$RATE" \
        -cpu-used 6 \
        -crf 30 \
        -tiles 2x2 \
        -g 120 \
        -an \
        "$OUT"

    echo "=== 计算 VMAF ==="
    ffmpeg -i "$SOURCE" -i "$OUT" \
        -lavfi "[0:v][1:v]libvmaf=model_path=version=vmaf_v0.6.1:log_path=${OUTPUT_DIR}/vmaf_${RATE}.json" \
        -f null -

    echo "码率 ${RATE} 完成，VMAF 报告: ${OUTPUT_DIR}/vmaf_${RATE}.json"
done

echo "全部完成。汇总 VMAF："
for RATE in "${RATES[@]}"; do
    SCORE=$(python3 -c "
import json
d = json.load(open('${OUTPUT_DIR}/vmaf_${RATE}.json'))
print(f'{d[\"pooled_metrics\"][\"vmaf\"][\"mean\"]:.2f}')
")
    echo "  ${RATE} bps → VMAF ${SCORE}"
done

# macOS
brew install ffmpeg libvmaf

# Ubuntu/Debian
sudo apt install ffmpeg libvmaf-dev

#!/usr/bin/env python3
"""codec_bench.py — AV1/AV2 编码对比基准"""
import subprocess, json, pathlib, statistics

SOURCE = pathlib.Path("source.mp4")
RESULTS = pathlib.Path("bench_results")
RESULTS.mkdir(exist_ok=True)

CODECS = {
    # AV2 编码器可用后取消注释
    # "av2": {"encoder": "libaom-av2", "crf": "30", "tiles": "2x2"},
    "av1": {"encoder": "libaom-av1", "crf": "30", "tiles": "2x2"},
}

RATES = [1_000_000, 2_000_000, 4_000_000]  # bps

def encode(codec_name, cfg, rate):
    out = RESULTS / f"{codec_name}_{rate}.mp4"
    cmd = [
        "ffmpeg", "-y", "-i", str(SOURCE),
        "-c:v", cfg["encoder"],
        "-b:v", str(rate),
        "-cpu-used", "4",
        "-crf", cfg["crf"],
        "-tiles", cfg["tiles"],
        "-an", str(out),
    ]
    subprocess.run(cmd, check=True, capture_output=True)
    return out

def vmaf(ref, distorted):
    log = RESULTS / f"vmaf_{distorted.stem}.json"
    cmd = [
        "ffmpeg", "-i", str(ref), "-i", str(distorted),
        "-lavfi",
        f"libvmaf=model_path=version=vmaf_v0.6.1:log_path={log}",
        "-f", "null", "-",
    ]
    subprocess.run(cmd, check=True, capture_output=True)
    data = json.loads(log.read_text())
    return data["pooled_metrics"]["vmaf"]["mean"]

def main():
    print(f"{'Codec':<6} {'Rate':>10} {'VMAF':>8} {'SizeKB':>8}")
    print("-" * 36)
    for name, cfg in CODECS.items():
        for rate in RATES:
            out = encode(name, cfg, rate)
            score = vmaf(SOURCE, out)
            size_kb = out.stat().st_size / 1024
            print(f"{name:<6} {rate:>10} {score:>8.2f} {size_kb:>8.1f}")

if __name__ == "__main__":
    main()