diff --git a/docs/guide/output-and-naming.md b/docs/guide/output-and-naming.md
index 9706023e..977dff58 100644
--- a/docs/guide/output-and-naming.md
+++ b/docs/guide/output-and-naming.md
@@ -163,9 +163,9 @@ For custom templates there is also a standalone [`{part}`](../reference/configur
 
 | Variable | Meaning | Example |
 |---|---|---|
-| `audio` | Audio codec | `DDP`, `DD`, `AAC`, `DTS-X` |
+| `audio` | Audio codec; rename it with [`codec_names`](../reference/configuration/output.md#codec_names) | `DDP`, `DD`, `AAC`, `DTS-X` |
 | `audio_channels` | Channel layout; bed.LFE.heights when the track has height channels | `5.1`, `2.0`, `5.1.4` |
-| `audio_full` | Codec + channels combined | `DDP5.1`, `DTS-X.5.1.4` |
+| `audio_full` | Codec + channels combined; a name that ends in a digit gets a separator | `DDP5.1`, `DTS-X.5.1.4`, `AC-4.2.0` |
 | `atmos` | `Atmos` when any track carries JOC | `Atmos` |
 | `dual` | `DUAL` for two audio languages (see [`dual_multi_mode`](../reference/configuration/download.md#dual_multi_mode)) | `DUAL` |
 | `multi` | `MULTi` for more than two audio languages | `MULTi` |
diff --git a/docs/reference/configuration/index.md b/docs/reference/configuration/index.md
index 5848264e..1141e4e0 100644
--- a/docs/reference/configuration/index.md
+++ b/docs/reference/configuration/index.md
@@ -32,7 +32,7 @@ Where the file lives, how unshackle discovers it, and how to edit it:
 | [Directories](directories.md) | `directories`, `filenames`, `services_repo_force` |
 | [Services & authentication](services.md) | `services`, `credentials`, `firefox_cookies`, `remote_services`, `serve` |
 | [Download & processing](download.md) | `dl`, `continue_downloads`, `merge_segments`, `subtitle`, `audio`, `muxing`, `language_tags`, `dual_multi_mode`, `generate_dv_mode`, `hdr10plus_probe` |
-| [Output & naming](output.md) | `output_template`, `tag`, `tag_rules`, `tag_group_name`, `tag_imdb_tmdb`, `chapter_fallback_name`, `unicode_filenames` |
+| [Output & naming](output.md) | `output_template`, `tag`, `tag_rules`, `codec_names`, `tag_group_name`, `tag_imdb_tmdb`, `chapter_fallback_name`, `unicode_filenames` |
 | [DRM & CDM](drm.md) | `cdm`, `remote_cdm`, `decryption` |
 | [Network & proxy](network.md) | `network`, `headers`, `proxy_providers` |
 | [Key vaults](vaults.md) | `key_vaults`, `vault_timeout` |
diff --git a/docs/reference/configuration/output.md b/docs/reference/configuration/output.md
index 4ec5f02b..148ac617 100644
--- a/docs/reference/configuration/output.md
+++ b/docs/reference/configuration/output.md
@@ -69,6 +69,32 @@ folder-kind keys.
 | `chapter_fallback_name` | str | `""` | Fallback template for chapter names, e.g. `"Chapter {i:02}"`. |
 | `unicode_filenames` | bool | `false` | Allow Unicode in filenames; when `false`, names are ASCII-sanitised. |
 
+## `codec_names`
+
+- **Type:** `dict`  ·  **Default:** `{}`
+
+Renames the codec and HDR names in the filename. Each map key is a name that unshackle writes by
+default, and its value is the name to write instead. The map applies to the `video`, `audio`,
+and `hdr` [template variables](../../guide/output-and-naming.md#template-variables), and so
+also to `audio_full`. A name that is not in the map stays as it is, and an empty value removes
+the name. You can also set `codec_names` for one service under `services`.
+
+```yaml title="unshackle.yaml"
+codec_names:
+  DDP: EAC3      # DDP5.1  -> EAC3.5.1
+  DD: AC3        # DD5.1   -> AC3.5.1
+  H.265: HEVC    # H.265   -> HEVC
+  HDR10P: HDR10+ # DV.HDR10P -> DV.HDR10+
+```
+
+For `hdr`, unshackle renames each part of a Dolby Vision label separately, so `HDR10P` also
+changes `DV.HDR10P` to `DV.HDR10+`. When an audio name ends in a digit, `audio_full` puts a
+separator before the channels: `EAC3.5.1`, not `EAC35.1`.
+
+!!! note "`tag_rules` see the new names"
+    unshackle evaluates [`tag_rules`](#tag_rules) after the rename. With the example above, a
+    rule must match `audio: EAC3`, not `audio: DDP`.
+
 ## `tag_rules`
 
 - **Type:** `list`  ·  **Default:** `[]`
diff --git a/tests/conftest.py b/tests/conftest.py
index 9f2f616f..ae36af88 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -46,6 +46,12 @@ def default_muxing(monkeypatch: pytest.MonkeyPatch) -> None:
     monkeypatch.setattr(config, "muxing", {})
 
 
+@pytest.fixture(autouse=True)
+def default_codec_names(monkeypatch: pytest.MonkeyPatch) -> None:
+    """Name codecs with the built-in labels, whatever codec_names the local unshackle.yaml sets."""
+    monkeypatch.setattr(config, "codec_names", {})
+
+
 @pytest.fixture
 def mux_args(monkeypatch: pytest.MonkeyPatch) -> Callable[..., list[str]]:
     """Run Tracks.mux up to mkvmerge and return its arguments; ``ids`` is what the track ID probe reports."""
diff --git a/tests/core/test_audio_channel_naming.py b/tests/core/test_audio_channel_naming.py
index 700146bd..945b5ed6 100644
--- a/tests/core/test_audio_channel_naming.py
+++ b/tests/core/test_audio_channel_naming.py
@@ -6,6 +6,7 @@ import types
 
 import pytest
 
+from unshackle.core.config import config
 from unshackle.core.titles.movie import Movie
 
 
@@ -51,3 +52,42 @@ def test_a_height_layout_is_named_bed_lfe_heights() -> None:
 )
 def test_layouts_without_heights_are_unchanged(layout: str | None, expected: str) -> None:
     assert named("E-AC-3", layout)["audio_channels"] == expected
+
+
+@pytest.mark.parametrize(
+    ("fmt", "expected"),
+    [("E-AC-3", "DDP5.1"), ("AC-3", "DD5.1"), ("AC-4", "AC-4 5.1"), ("AAC", "AAC5.1")],
+)
+def test_a_name_ending_in_a_digit_is_spaced_from_the_channels(fmt: str, expected: str) -> None:
+    assert named(fmt, "L R C LFE Ls Rs")["audio_full"] == expected
+
+
+def test_codec_names_overrides_the_built_in_name(monkeypatch: pytest.MonkeyPatch) -> None:
+    """The override is keyed by the name the filename would carry, and AC3 still gets its separator."""
+    monkeypatch.setattr(config, "codec_names", {"DDP": "EAC3", "DD": "AC3"})
+    assert named("E-AC-3", "L R C LFE Ls Rs")["audio_full"] == "EAC3 5.1"
+    assert named("AC-3", "L R C LFE Ls Rs")["audio"] == "AC3"
+
+
+def test_codec_names_renames_video_and_each_hdr_part(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setattr(config, "codec_names", {"H.265": "HEVC", "HDR10P": "HDR10+", "DTS-X": "DTSX"})
+    video = types.SimpleNamespace(
+        width=3840,
+        height=2160,
+        format="HEVC",
+        scan_type="Progressive",
+        other_display_aspect_ratio=["16:9"],
+        hdr_format_commercial="HDR10+",
+        hdr_format="Dolby Vision, Version 1.0, Profile 8.1",
+        transfer_characteristics=None,
+        transfer_characteristics_original=None,
+        frame_rate="23.976",
+    )
+    movie = Movie(id_="movie-0001", service=DummyService, name="The Film", year=2024, language="en")
+    context = movie.build_base_template_context(types.SimpleNamespace(video_tracks=[video], audio_tracks=[]))
+    assert (context["video"], context["hdr"]) == ("HEVC", "DV.HDR10+")
+    assert named("DTS-UHD", "L C R LFE Ls Rs")["audio_full"] == "DTSX 5.1", "a renamed DTS-X keeps its separator"
+
+
+def test_a_missing_audio_format_does_not_break_naming() -> None:
+    assert named(None, "L R", channel_s=2)["audio_full"] == "2.0"  # type: ignore[arg-type]
diff --git a/unshackle/core/config.py b/unshackle/core/config.py
index 82646661..bbca1549 100644
--- a/unshackle/core/config.py
+++ b/unshackle/core/config.py
@@ -199,6 +199,9 @@ class Config:
 
         self.language_tags: dict = kwargs.get("language_tags") or {}
         self.tag_rules: list = kwargs.get("tag_rules") or []
+        self.codec_names: dict = kwargs.get("codec_names") or {}
+        if not isinstance(self.codec_names, dict):
+            raise SystemExit(f"ERROR: codec_names must be a mapping, not {self.codec_names!r}")
         self.dual_multi_mode: str = (kwargs.get("dual_multi_mode") or "strict").lower()
         self.generate_dv_mode: str = str(kwargs.get("generate_dv_mode") or "v29").lower()
         self.hdr10plus_probe: bool = kwargs.get("hdr10plus_probe", True)
diff --git a/unshackle/core/titles/title.py b/unshackle/core/titles/title.py
index d98be289..31c52617 100644
--- a/unshackle/core/titles/title.py
+++ b/unshackle/core/titles/title.py
@@ -16,6 +16,12 @@ from unshackle.core.constants import (
 from unshackle.core.tracks import Tracks
 
 
+def rename(name: Optional[str]) -> str:
+    """Return the user's `codec_names` override for a filename label, read here so per-service overrides are covered."""
+    value = config.codec_names.get(name, name) if name else name
+    return "" if value is None else str(value)
+
+
 class Title:
     def __init__(
         self, id_: Any, service: type, language: Optional[Union[str, Language]] = None, data: Optional[Any] = None
@@ -147,7 +153,7 @@ class Title:
                 {
                     "quality": f"{resolution}{scan_suffix}",
                     "resolution": str(resolution),
-                    "video": VIDEO_CODEC_MAP.get(primary_video_track.format, primary_video_track.format),
+                    "video": rename(VIDEO_CODEC_MAP.get(primary_video_track.format, primary_video_track.format)),
                 }
             )
 
@@ -167,6 +173,7 @@ class Title:
                 context["hdr"] = "HLG"
             else:
                 context["hdr"] = ""
+            context["hdr"] = ".".join(filter(None, map(rename, context["hdr"].split("."))))
 
             frame_rate = float(primary_video_track.frame_rate) if primary_video_track.frame_rate else 0.0
             context["hfr"] = "HFR" if frame_rate > 30 else ""
@@ -191,8 +198,9 @@ class Title:
                 channels_str = f"{len(positions) - heights - lfe}.{lfe}.{heights}"
             else:
                 channels_str = f"{channels:.1f}"
-            audio = AUDIO_CODEC_MAP.get(codec, codec)
-            spacer = " " if audio in SPACED_AUDIO_CODECS else ""
+            builtin = AUDIO_CODEC_MAP.get(codec, codec)
+            audio = rename(builtin)
+            spacer = " " if builtin in SPACED_AUDIO_CODECS or audio[-1:].isdigit() else ""
 
             context.update(
                 {