Stow transcode

CHANGELOG.md

@@ -9,10 +9,19 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- STOW-RS (DIMSE backend) additionally offers the uncompressed transfer syntaxes and decompresses instances if the PACS does not accept their transfer syntax (#83). Can be disabled with `stow-rs.uncompressed-fallback: false`.
+- JPEG 2000 and JPEG-LS pixel data can now be decoded, e.g. when transcoding WADO-RS responses. Building from source requires a C++ compiler and CMake.
+- STOW-RS responses include a `FailureReason` for each failed instance.
+
 ### Changed
 
+- STOW-RS responds with `202 Accepted` if some instances failed and with `409 Conflict` if all instances failed, instead of `200 OK`.
+- Failures to store an instance are logged as warnings.
+
 ### Fixed
 
+- STOW-RS (DIMSE backend) no longer reports an instance as stored if the PACS returned a failure status in the C-STORE-RSP.
+
 ## [0.3.4] - 2026-10-27
 
 ### Added

Cargo.toml

@@ -29,7 +29,7 @@ mimalloc = ["dep:mimalloc"]
 # DICOM processing
 dicom = "0.10.0"
 dicom-json = "0.10.0"
-dicom-pixeldata = { version = "0.10.0", features = ["image"] }
+dicom-pixeldata = { version = "0.10.0", features = ["image", "openjpeg-sys", "charls"] }
 sentry = { version = "0.45.0", features = ["tracing"] }
 
 # Serialization

Dockerfile

@@ -1,4 +1,8 @@
 FROM lukemathwalker/cargo-chef:latest-rust-1.94.1 AS chef
+# cmake builds CharLS (JPEG-LS codec)
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends cmake \
+    && rm -rf /var/lib/apt/lists/*
 WORKDIR /app
 
 FROM chef AS planner

Dockerfile-s3

@@ -1,5 +1,6 @@
 FROM rust:1.94.1-alpine3.23 AS builder
-RUN apk add musl-dev openssl-dev openssl-libs-static
+# g++, cmake and make build CharLS (JPEG-LS codec)
+RUN apk add musl-dev openssl-dev openssl-libs-static g++ cmake make
 
 WORKDIR /app
 

deny.toml

@@ -7,6 +7,7 @@ unsound = "all"
 ignore = [
     { id = "RUSTSEC-2021-0153", reason = "encoding is used by dicom-encoding (dicom-rs); no maintained replacement upstream yet" },
     { id = "RUSTSEC-2024-0436", reason = "paste is used by rav1e (image, via dicom-pixeldata); proc-macro only" },
+    { id = "RUSTSEC-2026-0440", reason = "astral-tokio-tar is used by testcontainers (dev-dependency only); no testcontainers release without it yet" },
 ]
 
 [licenses]

docs/topics/backend-dimse.md

@@ -127,6 +127,15 @@ sequenceDiagram
     end
 ```
 
+Each instance is offered in its own transfer syntax and, unless
+[`stow-rs.uncompressed-fallback`](configuration.md#dicomweb.stow-rs.uncompressed-fallback) is disabled,
+additionally in the uncompressed transfer syntaxes.
+If the PACS does not accept the original transfer syntax, the instance is decompressed before sending it.
+
+Instances that could not be stored are listed in the `FailedSOPSequence` of the response.
+The `FailureReason` contains the status of the C-STORE-RSP, `0xC122` if the instance could not be
+converted to an accepted transfer syntax, or `0x0110` for other errors (e.g. a rejected association).
+
 ### Resources
 
 | Resource | URI Template       | Support Status |

docs/topics/configuration.md

@@ -205,6 +205,7 @@ aets:
       timeout: 3000
     stow-rs:
       timeout: 3000
+      uncompressed-fallback: true
 ```
 
 Each AET (regardless of the backend) has additional settings specific to the DICOMweb endpoints.
@@ -244,6 +245,15 @@ Each AET (regardless of the backend) has additional settings specific to the DIC
     This is the timeout for a single operation (e.g. receiving a DIMSE-C response primitive).
     If you want to set a timeout for the total execution time, use the <code>server.http.request-timeout</code> option instead.
     </def>
+    <def title="stow-rs.uncompressed-fallback" id="dicomweb.stow-rs.uncompressed-fallback">
+    <b>DIMSE-backend only:</b>
+    Whether to also offer the uncompressed transfer syntaxes (Explicit and Implicit VR Little Endian) when storing an instance.
+    Instances are sent in their original transfer syntax whenever the PACS accepts it.
+    If the PACS only accepts the uncompressed transfer syntaxes, the instance is decompressed before sending it.
+    Supported compressions are JPEG, JPEG Lossless, JPEG-LS, JPEG 2000 and RLE.
+    If disabled, instances in a transfer syntax that the PACS does not accept fail to store.
+    Defaults to <code>true</code>.
+    </def>
 </deflist>
 
 ## S3 Backend Config

src/api/stgcmt/service.rs

@@ -1,5 +1,6 @@
+pub use crate::api::stow::FailedInstance;
 use crate::api::stow::InstanceReference;
-use crate::types::{UI, US};
+use crate::types::UI;
 use async_trait::async_trait;
 use axum::body::Body;
 use axum::http::{Response, StatusCode};
@@ -106,13 +107,6 @@ pub struct InstanceLocation {
 	pub series_instance_uid: UI,
 }
 
-/// An instance for which storage has not been committed.
-#[derive(Debug, Clone)]
-pub struct FailedInstance {
-	pub reference: InstanceReference,
-	pub failure_reason: US,
-}
-
 /// The result of a storage commitment request, once known.
 /// Storage Commitment Response Module.
 /// <https://dicom.nema.org/medical/dicom/current/output/chtml/part18/chapter_J.html#sect_J.2>

src/api/stow/routes.rs

@@ -63,10 +63,11 @@ async fn studies(
 		instances: receiver.boxed(),
 	};
 	let response = stow.store(request).await?;
+	let status = response.status_code();
 	let json = DicomJson::from(InMemDicomObject::from(response));
 
 	Ok(Response::builder()
-		.status(StatusCode::OK)
+		.status(status)
 		.header(CONTENT_TYPE, mime::APPLICATION_JSON.as_ref())
 		.body(Body::from(serde_json::to_string(&json).unwrap()))
 		.unwrap())