From: Limin Wang <lance.lmw...@gmail.com> In SMPTE ST 12-1: 2014 Sec 12.2, we need to mark the frame flag if the frame rate > 30FPS to avoid interoperability issues. It will be used by the encoder to identify even or odd frames and correctly calculate the frame number of the SEI TC.
--- libavdevice/decklink_common.h | 1 + libavdevice/decklink_dec.cpp | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/libavdevice/decklink_common.h b/libavdevice/decklink_common.h index bd68c7b..8ddc411 100644 --- a/libavdevice/decklink_common.h +++ b/libavdevice/decklink_common.h @@ -151,6 +151,7 @@ struct decklink_ctx { int channels; int audio_depth; unsigned long tc_seen; // used with option wait_for_tc + uint32_t last_tc; }; typedef enum { DIRECTION_IN, DIRECTION_OUT} decklink_direction_t; diff --git a/libavdevice/decklink_dec.cpp b/libavdevice/decklink_dec.cpp index dde68ff..a60c01b 100644 --- a/libavdevice/decklink_dec.cpp +++ b/libavdevice/decklink_dec.cpp @@ -884,12 +884,26 @@ HRESULT decklink_input_callback::VideoInputFrameArrived( int metadata_len; uint8_t* packed_metadata; AVTimecode tcr; + AVRational rate = ctx->video_st->r_frame_rate; if (av_timecode_init_from_string(&tcr, ctx->video_st->r_frame_rate, tc, ctx) >= 0) { uint32_t tc_data = av_timecode_get_smpte_from_framenum(&tcr, 0); int size = sizeof(uint32_t) * 4; uint32_t *sd = (uint32_t *)av_packet_new_side_data(&pkt, AV_PKT_DATA_S12M_TIMECODE, size); + /* set the field flag if frame rate > 30FPS */ + /* Refer to SMPTE ST 12-1:2014 Sec 12.2 */ + if (av_cmp_q(rate, (AVRational) {30, 1}) == 1) { + /* Odd frame */ + if (ctx->last_tc == tc_data) { + if (av_cmp_q(rate, (AVRational) {50, 1}) == 0) + tc_data |= (1 << 7); + else + tc_data |= (1 << 23); + } + } + ctx->last_tc = tc_data; + if (sd) { *sd = 1; // one TC *(sd + 1) = tc_data; // TC -- 2.9.4 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".