ffmpeg | branch: master | Ray Tiley <rayti...@gmail.com> | Sun Feb 11 16:16:45 2018 -0800| [c837cd3d4d11b7d304ff83a448831c81a53c8c25] | committer: Marton Balint
avdevice/decklink_dec: extract NTSC VANC This changes how NTSC VANC is extracted from the buffer. In NTSC the vanc data is interleaved between luma and chroma, and not just the luma as in high definition resolutions. In my testing this allows a decklink card encoding valid NTSC closed captions to pass the caption data to the x264 encoder. Updated with reviews from Devin Heitmueller and Marton Balint. Signed-off-by: Ray Tiley <rayti...@gmail.com> Signed-off-by: Marton Balint <c...@passwd.hu> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c837cd3d4d11b7d304ff83a448831c81a53c8c25 --- libavdevice/decklink_dec.cpp | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/libavdevice/decklink_dec.cpp b/libavdevice/decklink_dec.cpp index 5c116f2d13..c3bb46e18f 100644 --- a/libavdevice/decklink_dec.cpp +++ b/libavdevice/decklink_dec.cpp @@ -149,6 +149,17 @@ static void extract_luma_from_v210(uint16_t *dst, const uint8_t *src, int width) } } +static void unpack_v210(uint16_t *dst, const uint8_t *src, int width) +{ + int i; + for (i = 0; i < width * 2 / 3; i++) { + *dst++ = src[0] + ((src[1] & 3) << 8); + *dst++ = (src[1] >> 2) + ((src[2] & 15) << 6); + *dst++ = (src[2] >> 4) + ((src[3] & 63) << 4); + src += 4; + } +} + static uint8_t calc_parity_and_line_offset(int line) { uint8_t ret = (line < 313) << 5; @@ -752,9 +763,15 @@ HRESULT decklink_input_callback::VideoInputFrameArrived( for (i = vanc_line_numbers[idx].vanc_start; i <= vanc_line_numbers[idx].vanc_end; i++) { uint8_t *buf; if (vanc->GetBufferForVerticalBlankingLine(i, (void**)&buf) == S_OK) { - uint16_t luma_vanc[MAX_WIDTH_VANC]; - extract_luma_from_v210(luma_vanc, buf, videoFrame->GetWidth()); - txt_buf = get_metadata(avctx, luma_vanc, videoFrame->GetWidth(), + uint16_t vanc[MAX_WIDTH_VANC]; + size_t vanc_size = videoFrame->GetWidth(); + if (ctx->bmd_mode == bmdModeNTSC && videoFrame->GetWidth() * 2 <= MAX_WIDTH_VANC) { + vanc_size = vanc_size * 2; + unpack_v210(vanc, buf, videoFrame->GetWidth()); + } else { + extract_luma_from_v210(vanc, buf, videoFrame->GetWidth()); + } + txt_buf = get_metadata(avctx, vanc, vanc_size, txt_buf, sizeof(txt_buf0) - (txt_buf - txt_buf0), &pkt); } if (i == vanc_line_numbers[idx].field0_vanc_end) _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog