diff --git a/libavcodec/proresdec.c b/libavcodec/proresdec.c
index 2e0cbf1f26..ca465f4d8e 100644
--- a/libavcodec/proresdec.c
+++ b/libavcodec/proresdec.c
@@ -105,8 +105,6 @@ static av_cold int decode_init(AVCodecContext *avctx)
     ctx->total_slices     = 0;
     ctx->slice_data       = NULL;
 
-    avctx->pix_fmt = PIX_FMT_YUV422P10; // set default pixel format
-
     avctx->bits_per_raw_sample = PRORES_BITS_PER_SAMPLE;
     ff_proresdsp_init(&ctx->dsp);
 
diff --git a/tests/ref/fate/prores-alpha b/tests/ref/fate/prores-alpha
index f8df87deee..8ad611de6f 100644
--- a/tests/ref/fate/prores-alpha
+++ b/tests/ref/fate/prores-alpha
@@ -1,2 +1,2 @@
-0, 0, 12441600, 0x5188265d
+0, 0, 12441600, 0x79c18863
 0, 3003, 12441600, 0x79c18863