diff --git a/renumics/spotlight/dtypes/conversion.py b/renumics/spotlight/dtypes/conversion.py
index 21f129b4..1488b79f 100644
--- a/renumics/spotlight/dtypes/conversion.py
+++ b/renumics/spotlight/dtypes/conversion.py
@@ -38,22 +38,13 @@
 import PIL.Image
 import validators
 
-from renumics.spotlight import dtypes
+from renumics.spotlight import dtypes, media
 from renumics.spotlight.typing import PathOrUrlType, PathType
 from renumics.spotlight.cache import external_data_cache
 from renumics.spotlight.io import audio
 from renumics.spotlight.io.file import as_file
 from renumics.spotlight.media.exceptions import InvalidFile
 from renumics.spotlight.backend.exceptions import Problem
-from renumics.spotlight.dtypes import (
-    CategoryDType,
-    DType,
-    audio_dtype,
-    image_dtype,
-    mesh_dtype,
-    video_dtype,
-)
-from renumics.spotlight.media import Sequence1D, Image, Audio, Video, Mesh
 
 
 NormalizedValue = Union[
@@ -96,7 +87,7 @@ class ConversionFailed(Problem):
     def __init__(
         self,
         value: NormalizedValue,
-        dtype: DType,
+        dtype: dtypes.DType,
         reason: Optional[str] = None,
     ) -> None:
         super().__init__(
@@ -116,14 +107,14 @@ class NoConverterAvailable(Problem):
     No matching converter could be applied
     """
 
-    def __init__(self, value: NormalizedValue, dtype: DType) -> None:
+    def __init__(self, value: NormalizedValue, dtype: dtypes.DType) -> None:
         msg = f"No Converter for {type(value)} -> {dtype}"
         super().__init__(title="No matching converter", detail=msg, status_code=422)
 
 
 N = TypeVar("N", bound=NormalizedValue)
 
-Converter = Callable[[N, DType], ConvertedValue]
+Converter = Callable[[N, dtypes.DType], ConvertedValue]
 _converters_table: Dict[
     Type[NormalizedValue], Dict[str, List[Converter]]
 ] = defaultdict(lambda: defaultdict(list))
@@ -176,7 +167,10 @@ def _decorate(func: Converter[N]) -> Converter[N]:
 
 
 def convert_to_dtype(
-    value: NormalizedValue, dtype: DType, simple: bool = False, check: bool = True
+    value: NormalizedValue,
+    dtype: dtypes.DType,
+    simple: bool = False,
+    check: bool = True,
 ) -> ConvertedValue:
     """
     Convert normalized type from data source to internal Spotlight DType
@@ -238,24 +232,24 @@ def convert_to_dtype(
 
 
 @convert("datetime")
-def _(value: datetime.datetime, _: DType) -> datetime.datetime:
+def _(value: datetime.datetime, _: dtypes.DType) -> datetime.datetime:
     return value
 
 
 @convert("datetime")
-def _(value: Union[str, np.str_], _: DType) -> Optional[datetime.datetime]:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> Optional[datetime.datetime]:
     if value == "":
         return None
     return datetime.datetime.fromisoformat(value)
 
 
 @convert("datetime")
-def _(value: np.datetime64, _: DType) -> Optional[datetime.datetime]:
+def _(value: np.datetime64, _: dtypes.DType) -> Optional[datetime.datetime]:
     return value.tolist()
 
 
 @convert("Category")
-def _(value: Union[str, np.str_], dtype: CategoryDType) -> int:
+def _(value: Union[str, np.str_], dtype: dtypes.CategoryDType) -> int:
     categories = dtype.categories
     if not categories:
         return -1
@@ -263,7 +257,7 @@ def _(value: Union[str, np.str_], dtype: CategoryDType) -> int:
 
 
 @convert("Category")
-def _(_: None, _dtype: CategoryDType) -> int:
+def _(_: None, _dtype: dtypes.CategoryDType) -> int:
     return -1
 
 
@@ -280,23 +274,23 @@ def _(
         np.uint32,
         np.uint64,
     ],
-    _: CategoryDType,
+    _: dtypes.CategoryDType,
 ) -> int:
     return int(value)
 
 
 @convert("Window")
-def _(value: list, _: DType) -> np.ndarray:
+def _(value: list, _: dtypes.DType) -> np.ndarray:
     return np.array(value, dtype=np.float64)
 
 
 @convert("Window")
-def _(value: np.ndarray, _: DType) -> np.ndarray:
+def _(value: np.ndarray, _: dtypes.DType) -> np.ndarray:
     return value.astype(np.float64)
 
 
 @convert("Window")
-def _(value: Union[str, np.str_], _: DType) -> np.ndarray:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> np.ndarray:
     try:
         obj = ast.literal_eval(value)
         array = np.array(obj, dtype=np.float64)
@@ -308,17 +302,17 @@ def _(value: Union[str, np.str_], _: DType) -> np.ndarray:
 
 
 @convert("Embedding", simple=False)
-def _(value: list, _: DType) -> np.ndarray:
+def _(value: list, _: dtypes.DType) -> np.ndarray:
     return np.array(value, dtype=np.float64)
 
 
 @convert("Embedding", simple=False)
-def _(value: np.ndarray, _: DType) -> np.ndarray:
+def _(value: np.ndarray, _: dtypes.DType) -> np.ndarray:
     return value.astype(np.float64)
 
 
 @convert("Embedding", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> np.ndarray:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> np.ndarray:
     try:
         obj = ast.literal_eval(value)
         array = np.array(obj, dtype=np.float64)
@@ -330,23 +324,23 @@ def _(value: Union[str, np.str_], _: DType) -> np.ndarray:
 
 
 @convert("Sequence1D", simple=False)
-def _(value: Union[np.ndarray, list], _: DType) -> np.ndarray:
-    return Sequence1D(value).encode()
+def _(value: Union[np.ndarray, list], _: dtypes.DType) -> np.ndarray:
+    return media.Sequence1D(value).encode()
 
 
 @convert("Sequence1D", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> np.ndarray:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> np.ndarray:
     try:
         obj = ast.literal_eval(value)
-        return Sequence1D(obj).encode()
+        return media.Sequence1D(obj).encode()
     except (ValueError, TypeError, SyntaxError, MemoryError, RecursionError):
         raise ConversionError("Cannot interpret string as a 1D sequence")
 
 
 @convert("Image", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> bytes:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> bytes:
     try:
-        if data := read_external_value(value, image_dtype):
+        if data := read_external_value(value, dtypes.image_dtype):
             return data.tolist()
     except InvalidFile:
         raise ConversionError()
@@ -354,26 +348,26 @@ def _(value: Union[str, np.str_], _: DType) -> bytes:
 
 
 @convert("Image", simple=False)
-def _(value: Union[bytes, np.bytes_], _: DType) -> bytes:
-    return Image.from_bytes(value).encode().tolist()
+def _(value: Union[bytes, np.bytes_], _: dtypes.DType) -> bytes:
+    return media.Image.from_bytes(value).encode().tolist()
 
 
 @convert("Image", simple=False)
-def _(value: np.ndarray, _: DType) -> bytes:
-    return Image(value).encode().tolist()
+def _(value: np.ndarray, _: dtypes.DType) -> bytes:
+    return media.Image(value).encode().tolist()
 
 
 @convert("Image", simple=False)
-def _(value: PIL.Image.Image, _: DType) -> bytes:
+def _(value: PIL.Image.Image, _: dtypes.DType) -> bytes:
     buffer = io.BytesIO()
     value.save(buffer, format="PNG")
     return buffer.getvalue()
 
 
 @convert("Audio", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> bytes:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> bytes:
     try:
-        if data := read_external_value(value, audio_dtype):
+        if data := read_external_value(value, dtypes.audio_dtype):
             return data.tolist()
     except (InvalidFile, IndexError, ValueError):
         raise ConversionError()
@@ -381,14 +375,14 @@ def _(value: Union[str, np.str_], _: DType) -> bytes:
 
 
 @convert("Audio", simple=False)
-def _(value: Union[bytes, np.bytes_], _: DType) -> bytes:
-    return Audio.from_bytes(value).encode().tolist()
+def _(value: Union[bytes, np.bytes_], _: dtypes.DType) -> bytes:
+    return media.Audio.from_bytes(value).encode().tolist()
 
 
 @convert("Video", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> bytes:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> bytes:
     try:
-        if data := read_external_value(value, video_dtype):
+        if data := read_external_value(value, dtypes.video_dtype):
             return data.tolist()
     except InvalidFile:
         raise ConversionError()
@@ -396,14 +390,14 @@ def _(value: Union[str, np.str_], _: DType) -> bytes:
 
 
 @convert("Video", simple=False)
-def _(value: Union[bytes, np.bytes_], _: DType) -> bytes:
-    return Video.from_bytes(value).encode().tolist()
+def _(value: Union[bytes, np.bytes_], _: dtypes.DType) -> bytes:
+    return media.Video.from_bytes(value).encode().tolist()
 
 
 @convert("Mesh", simple=False)
-def _(value: Union[str, np.str_], _: DType) -> bytes:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> bytes:
     try:
-        if data := read_external_value(value, mesh_dtype):
+        if data := read_external_value(value, dtypes.mesh_dtype):
             return data.tolist()
     except InvalidFile:
         raise ConversionError()
@@ -411,29 +405,29 @@ def _(value: Union[str, np.str_], _: DType) -> bytes:
 
 
 @convert("Mesh", simple=False)
-def _(value: Union[bytes, np.bytes_], _: DType) -> bytes:
+def _(value: Union[bytes, np.bytes_], _: dtypes.DType) -> bytes:
     return value
 
 
 # this should not be necessary
 @convert("Mesh", simple=False)  # type: ignore
-def _(value: trimesh.Trimesh, _: DType) -> bytes:
-    return Mesh.from_trimesh(value).encode().tolist()
+def _(value: trimesh.Trimesh, _: dtypes.DType) -> bytes:
+    return media.Mesh.from_trimesh(value).encode().tolist()
 
 
 @convert("Embedding", simple=True)
 @convert("Sequence1D", simple=True)
-def _(_: Union[np.ndarray, list, str, np.str_], _dtype: DType) -> str:
+def _(_: Union[np.ndarray, list, str, np.str_], _dtype: dtypes.DType) -> str:
     return "[...]"
 
 
 @convert("Image", simple=True)
-def _(_: np.ndarray, _dtype: DType) -> str:
+def _(_: np.ndarray, _dtype: dtypes.DType) -> str:
     return "[...]"
 
 
 @convert("Image", simple=True)
-def _(_: PIL.Image.Image, _dtype: DType) -> str:
+def _(_: PIL.Image.Image, _dtype: dtypes.DType) -> str:
     return "<PIL.Image>"
 
 
@@ -441,7 +435,7 @@ def _(_: PIL.Image.Image, _dtype: DType) -> str:
 @convert("Audio", simple=True)
 @convert("Video", simple=True)
 @convert("Mesh", simple=True)
-def _(value: Union[str, np.str_], _: DType) -> str:
+def _(value: Union[str, np.str_], _: dtypes.DType) -> str:
     return str(value)
 
 
@@ -449,19 +443,19 @@ def _(value: Union[str, np.str_], _: DType) -> str:
 @convert("Audio", simple=True)
 @convert("Video", simple=True)
 @convert("Mesh", simple=True)
-def _(_: Union[bytes, np.bytes_], _dtype: DType) -> str:
+def _(_: Union[bytes, np.bytes_], _dtype: dtypes.DType) -> str:
     return "<bytes>"
 
 
 # this should not be necessary
 @convert("Mesh", simple=True)  # type: ignore
-def _(_: trimesh.Trimesh, _dtype: DType) -> str:
+def _(_: trimesh.Trimesh, _dtype: dtypes.DType) -> str:
     return "<Trimesh>"
 
 
 def read_external_value(
     path_or_url: Optional[str],
-    dtype: DType,
+    dtype: dtypes.DType,
     target_format: Optional[str] = None,
     workdir: PathType = ".",
 ) -> Optional[np.void]:
@@ -498,7 +492,7 @@ def prepare_path_or_url(path_or_url: PathOrUrlType, workdir: PathType) -> str:
 
 def _decode_external_value(
     path_or_url: PathOrUrlType,
-    dtype: DType,
+    dtype: dtypes.DType,
     target_format: Optional[str] = None,
     workdir: PathType = ".",
 ) -> np.void:
@@ -528,7 +522,7 @@ def _decode_external_value(
             # Convert all other formats/codecs to flac.
             output_format, output_codec = "flac", "flac"
         else:
-            output_format, output_codec = Audio.get_format_codec(target_format)
+            output_format, output_codec = media.Audio.get_format_codec(target_format)
         if output_format == input_format and output_codec == input_codec:
             # Nothing to transcode
             if isinstance(file, str):
@@ -554,10 +548,10 @@ def _decode_external_value(
             ):
                 return np.void(file.read())
             # `image/tiff`s become blank in frontend, so convert them too.
-            return Image.from_file(file).encode(target_format)
+            return media.Image.from_file(file).encode(target_format)
 
     if dtypes.is_mesh_dtype(dtype):
-        return Mesh.from_file(path_or_url).encode(target_format)
+        return media.Mesh.from_file(path_or_url).encode(target_format)
     if dtypes.is_video_dtype(dtype):
-        return Video.from_file(path_or_url).encode(target_format)
+        return media.Video.from_file(path_or_url).encode(target_format)
     assert False