diff --git a/libavcodec/libx264.c b/libavcodec/libx264.c
index ca8f6c0..bad9351 100644
--- a/libavcodec/libx264.c
+++ b/libavcodec/libx264.c
@@ -289,6 +289,83 @@ static void reconfig_encoder(AVCodecContext *ctx, const AVFrame *frame)
     }
 }
 
+static int x264_encode_set_roi(const AVFrame *frame, AVCodecContext *ctx, int bit_depth)
+{
+    AVFrameSideData *sd = av_frame_get_side_data(frame, AV_FRAME_DATA_REGIONS_OF_INTEREST);
+    X264Context *x4 = ctx->priv_data;
+    int mbx = (frame->width + MB_SIZE - 1) / MB_SIZE;
+    int mby = (frame->height + MB_SIZE - 1) / MB_SIZE;
+    int qp_range = 51 + 6 * (bit_depth - 8);
+    int nb_rois;
+    const AVRegionOfInterest *roi;
+    uint32_t roi_size;
+    float *qoffsets;
+
+    if (!sd) {
+        return 0;
+    }
+
+    if (x4->params.rc.i_aq_mode == X264_AQ_NONE) {
+        if (!x4->roi_warned) {
+            x4->roi_warned = 1;
+            av_log(ctx, AV_LOG_WARNING, "Adaptive quantization must be enabled to use ROI encoding, skipping ROI.\n");
+        }
+        return 0;
+    }
+
+    if (frame->interlaced_frame != 0) {
+        if (!x4->roi_warned) {
+            x4->roi_warned = 1;
+            av_log(ctx, AV_LOG_WARNING, "interlaced_frame not supported for ROI encoding yet, skipping ROI.\n");
+        }
+        return 0;
+    }
+
+    roi = (const AVRegionOfInterest*)sd->data;
+    roi_size = roi->self_size;
+    if (!roi_size || sd->size % roi_size != 0) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid AVRegionOfInterest.self_size.\n");
+        return AVERROR(EINVAL);
+    }
+    nb_rois = sd->size / roi_size;
+
+    qoffsets = av_mallocz_array(mbx * mby, sizeof(*qoffsets));
+    if (!qoffsets)
+        return AVERROR(ENOMEM);
+
+    // This list must be iterated in reverse because the first
+    // region in the list applies when regions overlap.
+    for (int i = nb_rois - 1; i >= 0; i--) {
+        int startx, endx, starty, endy;
+        float qoffset;
+
+        roi = (const AVRegionOfInterest*)(sd->data + roi_size * i);
+
+        starty = FFMIN(mby, roi->top / MB_SIZE);
+        endy   = FFMIN(mby, (roi->bottom + MB_SIZE - 1)/ MB_SIZE);
+        startx = FFMIN(mbx, roi->left / MB_SIZE);
+        endx   = FFMIN(mbx, (roi->right + MB_SIZE - 1)/ MB_SIZE);
+
+        if (roi->qoffset.den == 0) {
+            av_free(qoffsets);
+            av_log(ctx, AV_LOG_ERROR, "AVRegionOfInterest.qoffset.den must not be zero.\n");
+            return AVERROR(EINVAL);
+        }
+        qoffset = roi->qoffset.num * 1.0f / roi->qoffset.den;
+        qoffset = av_clipf(qoffset * qp_range, -qp_range, +qp_range);
+
+        for (int y = starty; y < endy; y++) {
+            for (int x = startx; x < endx; x++) {
+                qoffsets[x + y*mbx] = qoffset;
+            }
+        }
+    }
+
+    x4->pic.prop.quant_offsets = qoffsets;
+    x4->pic.prop.quant_offsets_free = av_free;
+    return 0;
+}
+
 static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
                       int *got_packet)
 {
@@ -300,7 +377,6 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
     int bit_depth;
     int64_t wallclock = 0;
     X264Opaque *out_opaque;
-    AVFrameSideData *sd;
 
     x264_picture_init( &x4->pic );
     x4->pic.img.i_csp   = x4->params.i_csp;
@@ -367,73 +443,9 @@ static int X264_frame(AVCodecContext *ctx, AVPacket *pkt, const AVFrame *frame,
             }
         }
 
-        sd = av_frame_get_side_data(frame, AV_FRAME_DATA_REGIONS_OF_INTEREST);
-        if (sd) {
-            if (x4->params.rc.i_aq_mode == X264_AQ_NONE) {
-                if (!x4->roi_warned) {
-                    x4->roi_warned = 1;
-                    av_log(ctx, AV_LOG_WARNING, "Adaptive quantization must be enabled to use ROI encoding, skipping ROI.\n");
-                }
-            } else {
-                if (frame->interlaced_frame == 0) {
-                    int mbx = (frame->width + MB_SIZE - 1) / MB_SIZE;
-                    int mby = (frame->height + MB_SIZE - 1) / MB_SIZE;
-                    int qp_range = 51 + 6 * (bit_depth - 8);
-                    int nb_rois;
-                    const AVRegionOfInterest *roi;
-                    uint32_t roi_size;
-                    float *qoffsets;
-
-                    roi = (const AVRegionOfInterest*)sd->data;
-                    roi_size = roi->self_size;
-                    if (!roi_size || sd->size % roi_size != 0) {
-                        av_log(ctx, AV_LOG_ERROR, "Invalid AVRegionOfInterest.self_size.\n");
-                        return AVERROR(EINVAL);
-                    }
-                    nb_rois = sd->size / roi_size;
-
-                    qoffsets = av_mallocz_array(mbx * mby, sizeof(*qoffsets));
-                    if (!qoffsets)
-                        return AVERROR(ENOMEM);
-
-                    // This list must be iterated in reverse because the first
-                    // region in the list applies when regions overlap.
-                    for (int i = nb_rois - 1; i >= 0; i--) {
-                        int startx, endx, starty, endy;
-                        float qoffset;
-
-                        roi = (const AVRegionOfInterest*)(sd->data + roi_size * i);
-
-                        starty = FFMIN(mby, roi->top / MB_SIZE);
-                        endy   = FFMIN(mby, (roi->bottom + MB_SIZE - 1)/ MB_SIZE);
-                        startx = FFMIN(mbx, roi->left / MB_SIZE);
-                        endx   = FFMIN(mbx, (roi->right + MB_SIZE - 1)/ MB_SIZE);
-
-                        if (roi->qoffset.den == 0) {
-                            av_free(qoffsets);
-                            av_log(ctx, AV_LOG_ERROR, "AVRegionOfInterest.qoffset.den must not be zero.\n");
-                            return AVERROR(EINVAL);
-                        }
-                        qoffset = roi->qoffset.num * 1.0f / roi->qoffset.den;
-                        qoffset = av_clipf(qoffset * qp_range, -qp_range, +qp_range);
-
-                        for (int y = starty; y < endy; y++) {
-                            for (int x = startx; x < endx; x++) {
-                                qoffsets[x + y*mbx] = qoffset;
-                            }
-                        }
-                    }
-
-                    x4->pic.prop.quant_offsets = qoffsets;
-                    x4->pic.prop.quant_offsets_free = av_free;
-                } else {
-                    if (!x4->roi_warned) {
-                        x4->roi_warned = 1;
-                        av_log(ctx, AV_LOG_WARNING, "interlaced_frame not supported for ROI encoding yet, skipping ROI.\n");
-                    }
-                }
-            }
-        }
+        ret = x264_encode_set_roi(frame, ctx, bit_depth);
+        if (ret < 0)
+            return ret;
     }
 
     do {
