[FFmpeg-devel] [PATCH] lavc/videotoolboxenc: implement a53cc
Richard Kern
kernrj at gmail.com
Tue Oct 18 21:46:16 EEST 2016
> On Oct 18, 2016, at 2:30 PM, Aman Gupta <ffmpeg at tmm1.net> wrote:
>
>
>
> On Mon, Oct 17, 2016 at 6:03 PM, Aman Gupta <ffmpeg at tmm1.net <mailto:ffmpeg at tmm1.net>> wrote:
>
>
> On Mon, Oct 17, 2016 at 5:51 PM, Richard Kern <kernrj at gmail.com <mailto:kernrj at gmail.com>> wrote:
>
>> On Oct 17, 2016, at 8:47 PM, Aman Gupta <ffmpeg at tmm1.net <mailto: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.
>
> Actually, it looks like it's only happening when I use a specific video filter that I'm writing. Other filters seem fine, so the bug must be in my code somewhere.
>
> Still not sure why my filter was triggering the issue, since it's not doing anything that interesting..
>
> Nevertheless, here's a sample which reproduces the overflow with just a simple use of -c:v h264_videotoolbox:
>
> https://s3.amazonaws.com/tmm1/ccaptions/nightlynews3.ts <https://s3.amazonaws.com/tmm1/ccaptions/nightlynews3.ts>
I haven’t been able to repro with either sample. Can you check that it happens on master with no local changes? If so, please file a bug and post the full command along with output.
>
> It looks like an off-by-one somewhere, because if I increase out_buf_size by 1 the error goes away.
>
> Aman
>
>
> Aman
>
>
>>
>>
>>>
>>>
>>>
>>>>
>>>>
>>>> > 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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