fix(upscale): resolve realesrgan weights

Author: SysAdminDoc

CHANGELOG.md

@@ -118,6 +118,8 @@ record also lives in the git commit messages.
 - Styled-caption overlay encoding now drains FFmpeg stderr in a background
   thread while raw frames are piped to stdin, preventing stderr backpressure
   from deadlocking long renders.
+- The Real-ESRGAN upscale tier now resolves and caches official model weights
+  before constructing `RealESRGANer`, instead of passing `model_path=None`.
 - **Caption burn-in failed on every Windows drive-letter path.** The
   `subtitles=`/`ass=` filter value dropped colon escaping, so `C:/...` was
   parsed as filename `C`. Added `escape_filter_path()` with the verified

ROADMAP.md

@@ -23,10 +23,6 @@ history, not here.
   Why: six full :root token redefinitions (12, 4462, 5386, 13215, 15466, 17214), two divergent html.theme-light blocks (16701 vs 17628), three different :focus-visible rules, and a triplicated prefers-reduced-motion block — the effective theme is "whatever the last pass overrode" and ~⅓ of 18k lines is dead weight. Consolidate to one token block per theme; then retokenize the ~340 stray hex literals.
   Where: extension/com.opencut.panel/client/style.css
 
-- [ ] P2 — Real-ESRGAN "balanced" upscale tier is dead on arrival
-  Why: RealESRGANer(model_path=None) crashes in __init__ on every released package, and no pretrained weights are ever resolved; model_name is ignored. Resolve the weight file/URL and pass it.
-  Where: opencut/core/upscale_pro.py:122-126
-
 - [ ] P2 — Concat lists in ~17 feature modules still use unescaped, platform-codec writes
   Why: write_concat_list() now exists in helpers.py (UTF-8 + correct quote escaping) and the merge path uses it, but beat_cuts, ai_intro_gen, auto_dub_pipeline, photo_montage, instant_replay, cursor_zoom, event_recap, stream_highlights, video_360, generative_extend, auto_montage, glitch_effects, hook_generator, fit_to_fill, paper_edit, guest_compilation, stringout_reel still hand-roll open(path,"w") lists that break on apostrophes/non-ASCII names.
   Where: opencut/core/* (grep: "file '" writes); replace with helpers.write_concat_list

opencut/core/upscale_pro.py

@@ -15,12 +15,84 @@
 import os
 import subprocess
 import tempfile
+import urllib.request
 from typing import Callable, Dict, Optional
 
 from opencut.helpers import ensure_package, get_ffmpeg_path, get_video_info, run_ffmpeg
 
 logger = logging.getLogger("opencut")
 
+REALESRGAN_MODELS_DIR = os.path.join(os.path.expanduser("~"), ".opencut", "models")
+REALESRGAN_MODEL_SPECS = {
+    "RealESRGAN_x4plus": {
+        "filename": "RealESRGAN_x4plus.pth",
+        "url": "https://github.com/xinntao/Real-ESRGAN/releases/download/v0.1.0/RealESRGAN_x4plus.pth",
+        "scale": 4,
+        "num_block": 23,
+    },
+    "RealESRGAN_x2plus": {
+        "filename": "RealESRGAN_x2plus.pth",
+        "url": "https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.1/RealESRGAN_x2plus.pth",
+        "scale": 2,
+        "num_block": 23,
+    },
+    "RealESRGAN_x4plus_anime_6B": {
+        "filename": "RealESRGAN_x4plus_anime_6B.pth",
+        "url": "https://github.com/xinntao/Real-ESRGAN/releases/download/v0.2.2.4/RealESRGAN_x4plus_anime_6B.pth",
+        "scale": 4,
+        "num_block": 6,
+    },
+}
+_REALESRGAN_ALIASES = {
+    "realesrgan_x4plus": "RealESRGAN_x4plus",
+    "realesrgan-x4plus": "RealESRGAN_x4plus",
+    "x4plus": "RealESRGAN_x4plus",
+    "realesrgan_x2plus": "RealESRGAN_x2plus",
+    "realesrgan-x2plus": "RealESRGAN_x2plus",
+    "x2plus": "RealESRGAN_x2plus",
+    "realesrgan_x4plus_anime_6b": "RealESRGAN_x4plus_anime_6B",
+    "realesrgan-x4plus-anime-6b": "RealESRGAN_x4plus_anime_6B",
+    "x4plus_anime_6b": "RealESRGAN_x4plus_anime_6B",
+    "anime": "RealESRGAN_x4plus_anime_6B",
+}
+
+
+def _canonical_realesrgan_model_name(model_name: str) -> str:
+    if model_name in REALESRGAN_MODEL_SPECS:
+        return model_name
+    normalized = str(model_name or "").strip().lower().replace(" ", "_")
+    return _REALESRGAN_ALIASES.get(normalized, "RealESRGAN_x4plus")
+
+
+def _resolve_realesrgan_model_path(
+    model_name: str,
+    on_progress: Optional[Callable] = None,
+) -> str:
+    canonical_name = _canonical_realesrgan_model_name(model_name)
+    spec = REALESRGAN_MODEL_SPECS[canonical_name]
+    os.makedirs(REALESRGAN_MODELS_DIR, exist_ok=True)
+    model_path = os.path.join(REALESRGAN_MODELS_DIR, spec["filename"])
+    if os.path.isfile(model_path) and os.path.getsize(model_path) >= 1024:
+        return model_path
+
+    if on_progress:
+        on_progress(4, f"Downloading {canonical_name} weights...")
+
+    tmp_path = f"{model_path}.download"
+    try:
+        urllib.request.urlretrieve(spec["url"], tmp_path)
+        if not os.path.isfile(tmp_path) or os.path.getsize(tmp_path) < 1024:
+            raise RuntimeError(f"Downloaded Real-ESRGAN weights are empty: {spec['url']}")
+        os.replace(tmp_path, model_path)
+    except Exception:
+        try:
+            if os.path.exists(tmp_path):
+                os.unlink(tmp_path)
+        except OSError:
+            pass
+        raise
+    return model_path
+
 # ---------------------------------------------------------------------------
 # Availability
 # ---------------------------------------------------------------------------
@@ -119,9 +191,20 @@ def upscale_realesrgan(
     if on_progress:
         on_progress(5, "Loading Real-ESRGAN model...")
 
-    model = RRDBNet(num_in_ch=3, num_out_ch=3, num_feat=64, num_block=23, num_grow_ch=32, scale=4)
+    canonical_model_name = _canonical_realesrgan_model_name(model_name)
+    model_spec = REALESRGAN_MODEL_SPECS[canonical_model_name]
+    model_path = _resolve_realesrgan_model_path(canonical_model_name, on_progress)
+    model_scale = int(model_spec["scale"])
+    model = RRDBNet(
+        num_in_ch=3,
+        num_out_ch=3,
+        num_feat=64,
+        num_block=int(model_spec["num_block"]),
+        num_grow_ch=32,
+        scale=model_scale,
+    )
     upsampler = RealESRGANer(
-        scale=4, model_path=None, model=model, tile=tile,
+        scale=model_scale, model_path=model_path, model=model, tile=tile,
         half=torch.cuda.is_available(),
     )
 

tests/test_core_modules_batch2.py

@@ -846,6 +846,37 @@ def test_get_upscale_capabilities_returns_dict(self):
         caps = get_upscale_capabilities()
         self.assertIsInstance(caps, dict)
 
+    def test_realesrgan_model_resolver_downloads_official_weights(self):
+        from opencut.core import upscale_pro
+
+        old_models_dir = upscale_pro.REALESRGAN_MODELS_DIR
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            upscale_pro.REALESRGAN_MODELS_DIR = tmp_dir
+            try:
+                with patch("opencut.core.upscale_pro.urllib.request.urlretrieve") as mock_retrieve:
+                    def _fake_retrieve(url, target):
+                        Path(target).write_bytes(b"x" * 2048)
+                        return target, None
+
+                    mock_retrieve.side_effect = _fake_retrieve
+                    path = upscale_pro._resolve_realesrgan_model_path("realesrgan-x4plus")
+            finally:
+                upscale_pro.REALESRGAN_MODELS_DIR = old_models_dir
+
+        self.assertTrue(path.endswith("RealESRGAN_x4plus.pth"))
+        mock_retrieve.assert_called_once()
+        self.assertIn(
+            "https://github.com/xinntao/Real-ESRGAN/releases/download/v0.1.0/RealESRGAN_x4plus.pth",
+            mock_retrieve.call_args[0][0],
+        )
+
+    def test_upscale_realesrgan_uses_resolved_model_path(self):
+        from opencut.core import upscale_pro
+
+        source = Path(upscale_pro.__file__).read_text(encoding="utf-8")
+        self.assertIn("_resolve_realesrgan_model_path(canonical_model_name", source)
+        self.assertNotIn("model_path=None", source)
+
     @patch("opencut.core.upscale_pro.get_video_info",
            return_value={"width": 640, "height": 480})
     @patch("opencut.core.upscale_pro.run_ffmpeg")