[FFmpeg-devel] [PATCH] lavc/videotoolboxenc: implement a53cc
Richard Kern
kernrj at gmail.com
Tue Oct 18 03:51:12 EEST 2016
> On Oct 17, 2016, at 8:47 PM, Aman Gupta <ffmpeg at tmm1.net> wrote:
>
>
>
> On Mon, Oct 17, 2016 at 6:35 AM, Richard Kern <kernrj at gmail.com <mailto:kernrj at gmail.com>> wrote:
>
>> On Sep 19, 2016, at 10:30 AM, Aman Gupta <ffmpeg at tmm1.net <mailto:ffmpeg at tmm1.net>> wrote:
>>
>>
>>
>> On Monday, September 19, 2016, Richard Kern <kernrj at gmail.com <mailto:kernrj at gmail.com>> wrote:
>>
>>> On Sep 10, 2016, at 10:33 PM, Aman Gupta <ffmpeg at tmm1.net <>> wrote:
>>>
>>>
>>>
>>> On Sunday, September 11, 2016, Richard Kern <kernrj at gmail.com <>> wrote:
>>>
>>> > On Sep 8, 2016, at 4:19 AM, Aman Gupta <ffmpeg at tmm1.net <>> wrote:
>>> >
>>> > From: Aman Gupta <aman at tmm1.net <>>
>>> >
>>> > ---
>>> > libavcodec/videotoolboxenc.c | 76 ++++++++++++++++++++++++++++++++++++++------
>>> > 1 file changed, 67 insertions(+), 9 deletions(-)
>>> >
>>> > diff --git a/libavcodec/videotoolboxenc.c b/libavcodec/videotoolboxenc.c
>>> > index 4345ca3..859dde9 100644
>>> > --- a/libavcodec/videotoolboxenc.c
>>> > +++ b/libavcodec/videotoolboxenc.c
>>> > @@ -32,6 +32,7 @@
>>> > #include "libavutil/pixdesc.h"
>>> > #include "internal.h"
>>> > #include <pthread.h>
>>> > +#include "h264.h"
>>> >
>>> > #if !CONFIG_VT_BT2020
>>> > # define kCVImageBufferColorPrimaries_ITU_R_2020 CFSTR("ITU_R_2020")
>>> > @@ -55,8 +56,14 @@ typedef enum VTH264Entropy{
>>> >
>>> > static const uint8_t start_code[] = { 0, 0, 0, 1 };
>>> >
>>> > +typedef struct ExtraSEI {
>>> > + void *data;
>>> > + size_t size;
>>> > +} ExtraSEI;
>>> > +
>>> > typedef struct BufNode {
>>> > CMSampleBufferRef cm_buffer;
>>> > + ExtraSEI *sei;
>>> > struct BufNode* next;
>>> > int error;
>>> > } BufNode;
>>> > @@ -94,6 +101,7 @@ typedef struct VTEncContext {
>>> > bool flushing;
>>> > bool has_b_frames;
>>> > bool warned_color_range;
>>> > + bool a53_cc;
>>> > } VTEncContext;
>>> >
>>> > static int vtenc_populate_extradata(AVCodecContext *avctx,
>>> > @@ -136,7 +144,7 @@ static void set_async_error(VTEncContext *vtctx, int err)
>>> > pthread_mutex_unlock(&vtctx->lock);
>>> > }
>>> >
>>> > -static int vtenc_q_pop(VTEncContext *vtctx, bool wait, CMSampleBufferRef *buf)
>>> > +static int vtenc_q_pop(VTEncContext *vtctx, bool wait, CMSampleBufferRef *buf, ExtraSEI **sei)
>>> > {
>>> > BufNode *info;
>>> >
>>> > @@ -173,6 +181,12 @@ static int vtenc_q_pop(VTEncContext *vtctx, bool wait, CMSampleBufferRef *buf)
>>> > pthread_mutex_unlock(&vtctx->lock);
>>> >
>>> > *buf = info->cm_buffer;
>>> > + if (sei && *buf) {
>>> > + *sei = info->sei;
>>> > + } else if (info->sei) {
>>> > + if (info->sei->data) av_free(info->sei->data);
>>> > + av_free(info->sei);
>>> > + }
>>> > av_free(info);
>>> >
>>> > vtctx->frame_ct_out++;
>>> > @@ -180,7 +194,7 @@ static int vtenc_q_pop(VTEncContext *vtctx, bool wait, CMSampleBufferRef *buf)
>>> > return 0;
>>> > }
>>> >
>>> > -static void vtenc_q_push(VTEncContext *vtctx, CMSampleBufferRef buffer)
>>> > +static void vtenc_q_push(VTEncContext *vtctx, CMSampleBufferRef buffer, ExtraSEI *sei)
>>> > {
>>> > BufNode *info = av_malloc(sizeof(BufNode));
>>> > if (!info) {
>>> > @@ -190,6 +204,7 @@ static void vtenc_q_push(VTEncContext *vtctx, CMSampleBufferRef buffer)
>>> >
>>> > CFRetain(buffer);
>>> > info->cm_buffer = buffer;
>>> > + info->sei = sei;
>>> > info->next = NULL;
>>> >
>>> > pthread_mutex_lock(&vtctx->lock);
>>> > @@ -420,6 +435,7 @@ static void vtenc_output_callback(
>>> > {
>>> > AVCodecContext *avctx = ctx;
>>> > VTEncContext *vtctx = avctx->priv_data;
>>> > + ExtraSEI *sei = sourceFrameCtx;
>>> >
>>> > if (vtctx->async_error) {
>>> > if(sample_buffer) CFRelease(sample_buffer);
>>> > @@ -440,7 +456,7 @@ static void vtenc_output_callback(
>>> > }
>>> > }
>>> >
>>> > - vtenc_q_push(vtctx, sample_buffer);
>>> > + vtenc_q_push(vtctx, sample_buffer, sei);
>>> > }
>>> >
>>> > static int get_length_code_size(
>>> > @@ -1258,7 +1274,8 @@ static int copy_replace_length_codes(
>>> > static int vtenc_cm_to_avpacket(
>>> > AVCodecContext *avctx,
>>> > CMSampleBufferRef sample_buffer,
>>> > - AVPacket *pkt)
>>> > + AVPacket *pkt,
>>> > + ExtraSEI *sei)
>>> > {
>>> > VTEncContext *vtctx = avctx->priv_data;
>>> >
>>> > @@ -1269,6 +1286,7 @@ static int vtenc_cm_to_avpacket(
>>> > size_t header_size = 0;
>>> > size_t in_buf_size;
>>> > size_t out_buf_size;
>>> > + size_t sei_nalu_size = 0;
>>> > int64_t dts_delta;
>>> > int64_t time_base_num;
>>> > int nalu_count;
>>> > @@ -1298,9 +1316,14 @@ static int vtenc_cm_to_avpacket(
>>> > if(status)
>>> > return status;
>>> >
>>> > + if (sei) {
>>> > + sei_nalu_size = sizeof(start_code) + 3 + sei->size + 1;
>>> > + }
>>> > +
>>> > in_buf_size = CMSampleBufferGetTotalSampleSize(sample_buffer);
>>> > out_buf_size = header_size +
>>> > in_buf_size +
>>> > + sei_nalu_size +
>>> > nalu_count * ((int)sizeof(start_code) - (int)length_code_size);
>>> >
>>> > status = ff_alloc_packet2(avctx, pkt, out_buf_size, out_buf_size);
>>> > @@ -1317,7 +1340,7 @@ static int vtenc_cm_to_avpacket(
>>> > length_code_size,
>>> > sample_buffer,
>>> > pkt->data + header_size,
>>> > - pkt->size - header_size
>>> > + pkt->size - header_size - sei_nalu_size
>>> > );
>>> >
>>> > if (status) {
>>> > @@ -1325,6 +1348,19 @@ static int vtenc_cm_to_avpacket(
>>> > return status;
>>> > }
>>> >
>>> > + if (sei_nalu_size > 0) {
>>> > + uint8_t *sei_nalu = pkt->data + pkt->size - sei_nalu_size;
>>> > + memcpy(sei_nalu, start_code, sizeof(start_code));
>>> > + sei_nalu += sizeof(start_code);
>>> > + sei_nalu[0] = NAL_SEI;
>>> > + sei_nalu[1] = SEI_TYPE_USER_DATA_REGISTERED;
>>> > + sei_nalu[2] = sei->size;
>>> > + sei_nalu += 3;
>>> > + memcpy(sei_nalu, sei->data, sei->size);
>>> > + sei_nalu += sei->size;
>>> > + sei_nalu[0] = 1; // RBSP
>>> > + }
>>> > +
>>>
>>> SEI data should come after the parameter sets and before the other NAL units.
>>>
>>> Thanks. I have no prior experience with the h264 bitstream format so the help is much appreciated. Any advice on how to get the SEI inserted at the right spot?
>>>
>>> I also am unsure if I need to worry about start code emulation prevention within the SEI data.
>> The SEI data comes after the parameter sets and AUD NAL units (when they’re present). If I understand correctly, only one SEI NAL unit can be present per access unit (but it can contain multiple SEI messages). When the SEI NAL contains a buffering period SEI message it comes first in the list. The H.264 spec is available from the ITU website and contains the syntax for NAL units, SEI data, etc.
>>
>> Sorry I’ve been slow getting back to you. Hope this is helpful. If you’d prefer, I can reorder the SEI data later this week.
>>
>> No problem. If you get a chance to work up a patch, I would very much appreciate it.
>
> Pushed, thanks.
>
> Thanks!
>
> I tried a few samples which worked, but on others I'm getting "Error copying packet data: -1397118274" errors (looks like AVERROR_BUFFER_TOO_SMALL).
>
> Here's a sample that reproduces the error: https://s3.amazonaws.com/tmm1/ccaptions/nightlynews2.ts <https://s3.amazonaws.com/tmm1/ccaptions/nightlynews2.ts>Thanks, looking into it.
>
>
>>
>>
>>
>>>
>>>
>>> > if (is_key_frame) {
>>> > pkt->flags |= AV_PKT_FLAG_KEY;
>>> > }
>>> > @@ -1707,6 +1743,7 @@ static int vtenc_send_frame(AVCodecContext *avctx,
>>> > CMTime time;
>>> > CFDictionaryRef frame_dict;
>>> > CVPixelBufferRef cv_img = NULL;
>>> > + ExtraSEI *sei = NULL;
>>> > int status = create_cv_pixel_buffer(avctx, frame, &cv_img);
>>> >
>>> > if (status) return status;
>>> > @@ -1717,6 +1754,20 @@ static int vtenc_send_frame(AVCodecContext *avctx,
>>> > return status;
>>> > }
>>> >
>>> > + if (vtctx->a53_cc) {
>>> > + sei = av_mallocz(sizeof(*sei));
>>> > + if (!sei) {
>>> > + av_log(avctx, AV_LOG_ERROR, "Not enough memory for closed captions, skipping\n");
>>> > + } else {
>>> > + int ret = ff_alloc_a53_sei(frame, 0, &sei->data, &sei->size);
>>> > + if (ret < 0) {
>>> > + av_log(avctx, AV_LOG_ERROR, "Not enough memory for closed captions, skipping\n");
>>> > + av_free(sei);
>>> > + sei = NULL;
>>> > + }
>>> > + }
>>> > + }
>>> > +
>>> > time = CMTimeMake(frame->pts * avctx->time_base.num, avctx->time_base.den);
>>> > status = VTCompressionSessionEncodeFrame(
>>> > vtctx->session,
>>> > @@ -1724,7 +1775,7 @@ static int vtenc_send_frame(AVCodecContext *avctx,
>>> > time,
>>> > kCMTimeInvalid,
>>> > frame_dict,
>>> > - NULL,
>>> > + sei,
>>> > NULL
>>> > );
>>> >
>>> > @@ -1749,6 +1800,7 @@ static av_cold int vtenc_frame(
>>> > bool get_frame;
>>> > int status;
>>> > CMSampleBufferRef buf = NULL;
>>> > + ExtraSEI *sei = NULL;
>>> >
>>> > if (frame) {
>>> > status = vtenc_send_frame(avctx, vtctx, frame);
>>> > @@ -1785,11 +1837,15 @@ static av_cold int vtenc_frame(
>>> > goto end_nopkt;
>>> > }
>>> >
>>> > - status = vtenc_q_pop(vtctx, !frame, &buf);
>>> > + status = vtenc_q_pop(vtctx, !frame, &buf, &sei);
>>> > if (status) goto end_nopkt;
>>> > if (!buf) goto end_nopkt;
>>> >
>>> > - status = vtenc_cm_to_avpacket(avctx, buf, pkt);
>>> > + status = vtenc_cm_to_avpacket(avctx, buf, pkt, sei);
>>> > + if (sei) {
>>> > + if (sei->data) av_free(sei->data);
>>> > + av_free(sei);
>>> > + }
>>> > CFRelease(buf);
>>> > if (status) goto end_nopkt;
>>> >
>>> > @@ -1878,7 +1934,7 @@ static int vtenc_populate_extradata(AVCodecContext *avctx,
>>> > if (status)
>>> > goto pe_cleanup;
>>> >
>>> > - status = vtenc_q_pop(vtctx, 0, &buf);
>>> > + status = vtenc_q_pop(vtctx, 0, &buf, NULL);
>>> > if (status) {
>>> > av_log(avctx, AV_LOG_ERROR, "popping: %d\n", status);
>>> > goto pe_cleanup;
>>> > @@ -1976,6 +2032,8 @@ static const AVOption options[] = {
>>> > { "frames_after", "Other frames will come after the frames in this session. This helps smooth concatenation issues.",
>>> > OFFSET(frames_after), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VE },
>>> >
>>> > + { "a53cc", "Use A53 Closed Captions (if available)", OFFSET(a53_cc), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, VE },
>>> > +
>>> > { NULL },
>>> > };
>>> >
>>> > --
>>> > 2.8.1
>>>
>>> Patches should be made against the latest master branch. It doesn’t compile as-is.
>>>
>>> Oops, rebased locally for next patch.
>>>
>>>
>>> Thanks for your work. I look forward to an updated patch.
>>>
>>> >
>>> > _______________________________________________
>>> > ffmpeg-devel mailing list
>>> > <>ffmpeg-devel at ffmpeg.org <>
>>> > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel <http://ffmpeg.org/mailman/listinfo/ffmpeg-devel>
>
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