avcodec/mpegvideo_enc: Move MJPEG init checks to mjpegenc.c

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/mjpegenc.c

@@ -276,6 +276,16 @@ av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
 
     av_assert0(s->slice_context_count == 1);
 
+    if (s->codec_id == AV_CODEC_ID_AMV || (s->avctx->active_thread_type & FF_THREAD_SLICE))
+        s->huffman = 0;
+
+    if (s->mpv_flags & FF_MPV_FLAG_QP_RD) {
+        // Used to produce garbage with MJPEG.
+        av_log(s->avctx, AV_LOG_ERROR,
+               "QP RD is no longer compatible with MJPEG or AMV\n");
+        return AVERROR(EINVAL);
+    }
+
     /* The following check is automatically true for AMV,
      * but it doesn't hurt either. */
     ret = ff_mjpeg_encode_check_pix_fmt(s->avctx);

libavcodec/mpegvideo_enc.c

@@ -370,9 +370,6 @@ av_cold int ff_mpv_encode_init(AVCodecContext *avctx)
         return AVERROR(EINVAL);
     }
 
-    if (avctx->codec_id == AV_CODEC_ID_AMV || (avctx->active_thread_type & FF_THREAD_SLICE))
-        s->huffman = 0;
-
     if (s->intra_dc_precision > (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO ? 3 : 0)) {
         av_log(avctx, AV_LOG_ERROR, "intra dc precision too large\n");
         return AVERROR(EINVAL);
@@ -573,15 +570,6 @@ av_cold int ff_mpv_encode_init(AVCodecContext *avctx)
         return AVERROR(EINVAL);
     }
 
-    if ((s->mpv_flags & FF_MPV_FLAG_QP_RD) &&
-            (s->codec_id == AV_CODEC_ID_AMV ||
-             s->codec_id == AV_CODEC_ID_MJPEG)) {
-        // Used to produce garbage with MJPEG.
-        av_log(avctx, AV_LOG_ERROR,
-               "QP RD is no longer compatible with MJPEG or AMV\n");
-        return AVERROR(EINVAL);
-    }
-
     if (s->scenechange_threshold < 1000000000 &&
         (avctx->flags & AV_CODEC_FLAG_CLOSED_GOP)) {
         av_log(avctx, AV_LOG_ERROR,