[FFmpeg-devel] [PATCH v2] libavcodec/v4l2_buffers.c: set AVFrame interlaced flags

[Scott Theisen]

Originally from:
https://github.com/MythTV/mythtv/commit/669955c6cb29196b4b5120451b5b998d67a65749
---
 libavcodec/v4l2_buffers.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/libavcodec/v4l2_buffers.c b/libavcodec/v4l2_buffers.c
index 23474ee143..85dfb40093 100644
--- a/libavcodec/v4l2_buffers.c
+++ b/libavcodec/v4l2_buffers.c
@@ -210,6 +210,25 @@ static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
     return AVCOL_TRC_UNSPECIFIED;
 }
 
+static void v4l2_get_interlacing(AVFrame *frame, V4L2Buffer *buf)
+{
+    enum v4l2_field field;
+    field = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.field :
+        buf->context->format.fmt.pix.field;
+
+    if (field == V4L2_FIELD_INTERLACED || field == V4L2_FIELD_INTERLACED_TB) {
+        frame->flags |=  AV_FRAME_FLAG_INTERLACED;
+        frame->flags |=  AV_FRAME_FLAG_TOP_FIELD_FIRST;
+    } else if (field == V4L2_FIELD_INTERLACED_BT) {
+        frame->flags |=  AV_FRAME_FLAG_INTERLACED;
+        frame->flags &= ~AV_FRAME_FLAG_TOP_FIELD_FIRST;
+    } else {
+        frame->flags &= ~AV_FRAME_FLAG_INTERLACED;
+        frame->flags &= ~AV_FRAME_FLAG_TOP_FIELD_FIRST;
+    }
+}
+
 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
 {
     V4L2Buffer* avbuf = opaque;
@@ -434,6 +453,7 @@ int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
     frame->color_trc = v4l2_get_color_trc(avbuf);
     frame->pts = v4l2_get_pts(avbuf);
     frame->pkt_dts = AV_NOPTS_VALUE;
+    v4l2_get_interlacing(frame, avbuf);
 
     /* these values are updated also during re-init in v4l2_process_driver_event */
     frame->height = avbuf->context->height;
-- 
2.43.0