diff --git a/src/media/png-encode.ts b/src/media/png-encode.ts
index a456ac30a2e..6799f0ea259 100644
--- a/src/media/png-encode.ts
+++ b/src/media/png-encode.ts
@@ -17,7 +17,7 @@ const CRC_TABLE = (() => {
 })();
 
 /** Compute CRC32 checksum for a buffer (used in PNG chunk encoding). */
-export function crc32(buf: Buffer): number {
+function crc32(buf: Buffer): number {
   let crc = 0xffffffff;
   for (let i = 0; i < buf.length; i += 1) {
     crc = CRC_TABLE[(crc ^ buf[i]) & 0xff] ^ (crc >>> 8);
@@ -26,7 +26,7 @@ export function crc32(buf: Buffer): number {
 }
 
 /** Create a PNG chunk with type, data, and CRC. */
-export function pngChunk(type: string, data: Buffer): Buffer {
+function pngChunk(type: string, data: Buffer): Buffer {
   const typeBuf = Buffer.from(type, "ascii");
   const len = Buffer.alloc(4);
   len.writeUInt32BE(data.length, 0);
diff --git a/src/media/qr-image.ts b/src/media/qr-image.ts
index d08b2fcb1da..6ab374b7240 100644
--- a/src/media/qr-image.ts
+++ b/src/media/qr-image.ts
@@ -10,18 +10,18 @@ const MIN_QR_PNG_MARGIN_MODULES = 0;
 const MAX_QR_PNG_MARGIN_MODULES = 16;
 const QR_PNG_DATA_URL_PREFIX = "data:image/png;base64,";
 
-export type QrPngRenderOptions = {
+type QrPngRenderOptions = {
   scale?: number;
   marginModules?: number;
 };
 
-export type QrPngTempFileOptions = QrPngRenderOptions & {
+type QrPngTempFileOptions = QrPngRenderOptions & {
   tmpRoot: string;
   dirPrefix: string;
   fileName?: string;
 };
 
-export type QrPngTempFile = {
+type QrPngTempFile = {
   filePath: string;
   dirPath: string;
   mediaLocalRoots: string[];