/*
* This file is part of FFmpeg .
*
* FFmpeg is free software ; you can redistribute it and / or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation ; either
* version 2.1 of the License , or ( at your option ) any later version .
*
* FFmpeg is distributed in the hope that it will be useful ,
* but WITHOUT ANY WARRANTY ; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE . See the GNU
* Lesser General Public License for more details .
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg ; if not , write to the Free Software
* Foundation , Inc . , 51 Franklin Street , Fifth Floor , Boston , MA 02110 - 1301 USA
*/
# include "libavutil/internal.h"
# include "avcodec.h"
# include "internal.h"
# include "nvenc.h"
# define OFFSET(x) offsetof(NvencContext, x)
# define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options [ ] = {
{ " preset " , " Set the encoding preset " , OFFSET ( preset ) , AV_OPT_TYPE_INT , { . i64 = PRESET_MEDIUM } , PRESET_DEFAULT , PRESET_LOSSLESS_HP , VE , " preset " } ,
{ " default " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_DEFAULT } , 0 , 0 , VE , " preset " } ,
{ " slow " , " hq 2 passes " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_SLOW } , 0 , 0 , VE , " preset " } ,
{ " medium " , " hq 1 pass " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_MEDIUM } , 0 , 0 , VE , " preset " } ,
{ " fast " , " hp 1 pass " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_FAST } , 0 , 0 , VE , " preset " } ,
{ " hp " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_HP } , 0 , 0 , VE , " preset " } ,
{ " hq " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_HQ } , 0 , 0 , VE , " preset " } ,
{ " bd " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_BD } , 0 , 0 , VE , " preset " } ,
{ " ll " , " low latency " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_LOW_LATENCY_DEFAULT } , 0 , 0 , VE , " preset " } ,
{ " llhq " , " low latency hq " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_LOW_LATENCY_HQ } , 0 , 0 , VE , " preset " } ,
{ " llhp " , " low latency hp " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_LOW_LATENCY_HP } , 0 , 0 , VE , " preset " } ,
{ " lossless " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_LOSSLESS_DEFAULT } , 0 , 0 , VE , " preset " } ,
{ " losslesshp " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = PRESET_LOSSLESS_HP } , 0 , 0 , VE , " preset " } ,
{ " profile " , " Set the encoding profile " , OFFSET ( profile ) , AV_OPT_TYPE_INT , { . i64 = NV_ENC_H264_PROFILE_MAIN } , NV_ENC_H264_PROFILE_BASELINE , NV_ENC_H264_PROFILE_HIGH_444P , VE , " profile " } ,
{ " baseline " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_PROFILE_BASELINE } , 0 , 0 , VE , " profile " } ,
{ " main " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_PROFILE_MAIN } , 0 , 0 , VE , " profile " } ,
{ " high " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_PROFILE_HIGH } , 0 , 0 , VE , " profile " } ,
{ " high444p " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_PROFILE_HIGH_444P } , 0 , 0 , VE , " profile " } ,
{ " level " , " Set the encoding level restriction " , OFFSET ( level ) , AV_OPT_TYPE_INT , { . i64 = NV_ENC_LEVEL_AUTOSELECT } , NV_ENC_LEVEL_AUTOSELECT , NV_ENC_LEVEL_H264_51 , VE , " level " } ,
{ " auto " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_AUTOSELECT } , 0 , 0 , VE , " level " } ,
{ " 1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_1 } , 0 , 0 , VE , " level " } ,
{ " 1.0 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_1 } , 0 , 0 , VE , " level " } ,
{ " 1b " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_1b } , 0 , 0 , VE , " level " } ,
{ " 1.0b " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_1b } , 0 , 0 , VE , " level " } ,
{ " 1.1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_11 } , 0 , 0 , VE , " level " } ,
{ " 1.2 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_12 } , 0 , 0 , VE , " level " } ,
{ " 1.3 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_13 } , 0 , 0 , VE , " level " } ,
{ " 2 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_2 } , 0 , 0 , VE , " level " } ,
{ " 2.0 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_2 } , 0 , 0 , VE , " level " } ,
{ " 2.1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_21 } , 0 , 0 , VE , " level " } ,
{ " 2.2 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_22 } , 0 , 0 , VE , " level " } ,
{ " 3 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_3 } , 0 , 0 , VE , " level " } ,
{ " 3.0 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_3 } , 0 , 0 , VE , " level " } ,
{ " 3.1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_31 } , 0 , 0 , VE , " level " } ,
{ " 3.2 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_32 } , 0 , 0 , VE , " level " } ,
{ " 4 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_4 } , 0 , 0 , VE , " level " } ,
{ " 4.0 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_4 } , 0 , 0 , VE , " level " } ,
{ " 4.1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_41 } , 0 , 0 , VE , " level " } ,
{ " 4.2 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_42 } , 0 , 0 , VE , " level " } ,
{ " 5 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_5 } , 0 , 0 , VE , " level " } ,
{ " 5.0 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_5 } , 0 , 0 , VE , " level " } ,
{ " 5.1 " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_LEVEL_H264_51 } , 0 , 0 , VE , " level " } ,
{ " rc " , " Override the preset rate-control " , OFFSET ( rc ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , INT_MAX , VE , " rc " } ,
{ " constqp " , " Constant QP mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_CONSTQP } , 0 , 0 , VE , " rc " } ,
{ " vbr " , " Variable bitrate mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_VBR } , 0 , 0 , VE , " rc " } ,
{ " cbr " , " Constant bitrate mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_CBR } , 0 , 0 , VE , " rc " } ,
{ " vbr_minqp " , " Variable bitrate mode with MinQP (deprecated) " , 0 , AV_OPT_TYPE_CONST , { . i64 = RCD ( NV_ENC_PARAMS_RC_VBR_MINQP ) } , 0 , 0 , VE , " rc " } ,
{ " ll_2pass_quality " , " Multi-pass optimized for image quality (deprecated) " ,
0 , AV_OPT_TYPE_CONST , { . i64 = RCD ( NV_ENC_PARAMS_RC_2_PASS_QUALITY ) } , 0 , 0 , VE , " rc " } ,
{ " ll_2pass_size " , " Multi-pass optimized for constant frame size (deprecated) " ,
0 , AV_OPT_TYPE_CONST , { . i64 = RCD ( NV_ENC_PARAMS_RC_2_PASS_FRAMESIZE_CAP ) } , 0 , 0 , VE , " rc " } ,
{ " vbr_2pass " , " Multi-pass variable bitrate mode (deprecated) " , 0 , AV_OPT_TYPE_CONST , { . i64 = RCD ( NV_ENC_PARAMS_RC_2_PASS_VBR ) } , 0 , 0 , VE , " rc " } ,
{ " cbr_ld_hq " , " Constant bitrate low delay high quality mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_CBR_LOWDELAY_HQ } , 0 , 0 , VE , " rc " } ,
{ " cbr_hq " , " Constant bitrate high quality mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_CBR_HQ } , 0 , 0 , VE , " rc " } ,
{ " vbr_hq " , " Variable bitrate high quality mode " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_PARAMS_RC_VBR_HQ } , 0 , 0 , VE , " rc " } ,
{ " rc-lookahead " , " Number of frames to look ahead for rate-control " ,
OFFSET ( rc_lookahead ) , AV_OPT_TYPE_INT , { . i64 = 0 } , 0 , INT_MAX , VE } ,
{ " surfaces " , " Number of concurrent surfaces " , OFFSET ( nb_surfaces ) , AV_OPT_TYPE_INT , { . i64 = 0 } , 0 , MAX_REGISTERED_FRAMES , VE } ,
{ " cbr " , " Use cbr encoding mode " , OFFSET ( cbr ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " 2pass " , " Use 2pass encoding mode " , OFFSET ( twopass ) , AV_OPT_TYPE_BOOL , { . i64 = - 1 } , - 1 , 1 , VE } ,
{ " gpu " , " Selects which NVENC capable GPU to use. First GPU is 0, second is 1, and so on. " ,
OFFSET ( device ) , AV_OPT_TYPE_INT , { . i64 = ANY_DEVICE } , - 2 , INT_MAX , VE , " gpu " } ,
{ " any " , " Pick the first device available " , 0 , AV_OPT_TYPE_CONST , { . i64 = ANY_DEVICE } , 0 , 0 , VE , " gpu " } ,
{ " list " , " List the available devices " , 0 , AV_OPT_TYPE_CONST , { . i64 = LIST_DEVICES } , 0 , 0 , VE , " gpu " } ,
{ " delay " , " Delay frame output by the given amount of frames " ,
OFFSET ( async_depth ) , AV_OPT_TYPE_INT , { . i64 = INT_MAX } , 0 , INT_MAX , VE } ,
{ " no-scenecut " , " When lookahead is enabled, set this to 1 to disable adaptive I-frame insertion at scene cuts " ,
OFFSET ( no_scenecut ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " forced-idr " , " If forcing keyframes, force them as IDR frames. " ,
OFFSET ( forced_idr ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , - 1 , 1 , VE } ,
{ " b_adapt " , " When lookahead is enabled, set this to 0 to disable adaptive B-frame decision " ,
OFFSET ( b_adapt ) , AV_OPT_TYPE_BOOL , { . i64 = 1 } , 0 , 1 , VE } ,
{ " spatial-aq " , " set to 1 to enable Spatial AQ " , OFFSET ( aq ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " spatial_aq " , " set to 1 to enable Spatial AQ " , OFFSET ( aq ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " temporal-aq " , " set to 1 to enable Temporal AQ " , OFFSET ( temporal_aq ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " temporal_aq " , " set to 1 to enable Temporal AQ " , OFFSET ( temporal_aq ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " zerolatency " , " Set 1 to indicate zero latency operation (no reordering delay) " ,
OFFSET ( zerolatency ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " nonref_p " , " Set this to 1 to enable automatic insertion of non-reference P-frames " ,
OFFSET ( nonref_p ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " strict_gop " , " Set 1 to minimize GOP-to-GOP rate fluctuations " ,
OFFSET ( strict_gop ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " aq-strength " , " When Spatial AQ is enabled, this field is used to specify AQ strength. AQ strength scale is from 1 (low) - 15 (aggressive) " ,
OFFSET ( aq_strength ) , AV_OPT_TYPE_INT , { . i64 = 8 } , 1 , 15 , VE } ,
{ " cq " , " Set target quality level (0 to 51, 0 means automatic) for constant quality mode in VBR rate control " ,
OFFSET ( quality ) , AV_OPT_TYPE_FLOAT , { . dbl = 0. } , 0. , 51. , VE } ,
{ " aud " , " Use access unit delimiters " , OFFSET ( aud ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " bluray-compat " , " Bluray compatibility workarounds " , OFFSET ( bluray_compat ) , AV_OPT_TYPE_BOOL , { . i64 = 0 } , 0 , 1 , VE } ,
{ " init_qpP " , " Initial QP value for P frame " , OFFSET ( init_qp_p ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , 51 , VE } ,
{ " init_qpB " , " Initial QP value for B frame " , OFFSET ( init_qp_b ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , 51 , VE } ,
{ " init_qpI " , " Initial QP value for I frame " , OFFSET ( init_qp_i ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , 51 , VE } ,
{ " qp " , " Constant quantization parameter rate control method " ,
OFFSET ( cqp ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , 51 , VE } ,
{ " weighted_pred " , " Set 1 to enable weighted prediction " ,
OFFSET ( weighted_pred ) , AV_OPT_TYPE_INT , { . i64 = 0 } , 0 , 1 , VE } ,
{ " coder " , " Coder type " , OFFSET ( coder ) , AV_OPT_TYPE_INT , { . i64 = - 1 } , - 1 , 2 , VE , " coder " } ,
{ " default " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = - 1 } , 0 , 0 , VE , " coder " } ,
{ " auto " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_ENTROPY_CODING_MODE_AUTOSELECT } , 0 , 0 , VE , " coder " } ,
{ " cabac " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_ENTROPY_CODING_MODE_CABAC } , 0 , 0 , VE , " coder " } ,
{ " cavlc " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_ENTROPY_CODING_MODE_CAVLC } , 0 , 0 , VE , " coder " } ,
{ " ac " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_ENTROPY_CODING_MODE_CABAC } , 0 , 0 , VE , " coder " } ,
{ " vlc " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_H264_ENTROPY_CODING_MODE_CAVLC } , 0 , 0 , VE , " coder " } ,
# ifdef NVENC_HAVE_BFRAME_REF_MODE
{ " b_ref_mode " , " Use B frames as references " , OFFSET ( b_ref_mode ) , AV_OPT_TYPE_INT , { . i64 = NV_ENC_BFRAME_REF_MODE_DISABLED } , NV_ENC_BFRAME_REF_MODE_DISABLED , NV_ENC_BFRAME_REF_MODE_MIDDLE , VE , " b_ref_mode " } ,
{ " disabled " , " B frames will not be used for reference " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_BFRAME_REF_MODE_DISABLED } , 0 , 0 , VE , " b_ref_mode " } ,
{ " each " , " Each B frame will be used for reference " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_BFRAME_REF_MODE_EACH } , 0 , 0 , VE , " b_ref_mode " } ,
{ " middle " , " Only (number of B frames)/2 will be used for reference " , 0 , AV_OPT_TYPE_CONST , { . i64 = NV_ENC_BFRAME_REF_MODE_MIDDLE } , 0 , 0 , VE , " b_ref_mode " } ,
# else
{ " b_ref_mode " , " (not supported) " , OFFSET ( b_ref_mode ) , AV_OPT_TYPE_INT , { . i64 = 0 } , 0 , INT_MAX , VE , " b_ref_mode " } ,
{ " disabled " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = 0 } , 0 , 0 , VE , " b_ref_mode " } ,
{ " each " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = 1 } , 0 , 0 , VE , " b_ref_mode " } ,
{ " middle " , " " , 0 , AV_OPT_TYPE_CONST , { . i64 = 2 } , 0 , 0 , VE , " b_ref_mode " } ,
# endif
{ " a53cc " , " Use A53 Closed Captions (if available) " , OFFSET ( a53_cc ) , AV_OPT_TYPE_BOOL , { . i64 = 1 } , 0 , 1 , VE } ,
{ " dpb_size " , " Specifies the DPB size used for encoding (0 means automatic) " ,
OFFSET ( dpb_size ) , AV_OPT_TYPE_INT , { . i64 = 0 } , 0 , INT_MAX , VE } ,
{ NULL }
} ;
static const AVCodecDefault defaults [ ] = {
{ " b " , " 2M " } ,
{ " qmin " , " -1 " } ,
{ " qmax " , " -1 " } ,
{ " qdiff " , " -1 " } ,
{ " qblur " , " -1 " } ,
{ " qcomp " , " -1 " } ,
{ " g " , " 250 " } ,
{ " bf " , " 0 " } ,
{ " refs " , " 0 " } ,
{ NULL } ,
} ;
# if FF_API_NVENC_OLD_NAME
static av_cold int nvenc_old_init ( AVCodecContext * avctx )
{
av_log ( avctx , AV_LOG_WARNING , " This encoder is deprecated, use 'h264_nvenc' instead \n " ) ;
return ff_nvenc_encode_init ( avctx ) ;
}
# if CONFIG_NVENC_ENCODER
static const AVClass nvenc_class = {
. class_name = " nvenc " ,
. item_name = av_default_item_name ,
. option = options ,
. version = LIBAVUTIL_VERSION_INT ,
} ;
AVCodec ff_nvenc_encoder = {
. name = " nvenc " ,
. long_name = NULL_IF_CONFIG_SMALL ( " NVIDIA NVENC H.264 encoder " ) ,
. type = AVMEDIA_TYPE_VIDEO ,
. id = AV_CODEC_ID_H264 ,
. init = nvenc_old_init ,
. send_frame = ff_nvenc_send_frame ,
. receive_packet = ff_nvenc_receive_packet ,
. encode2 = ff_nvenc_encode_frame ,
. close = ff_nvenc_encode_close ,
avcodec: Add explicit capability flag for encoder flushing
Previously, there was no way to flush an encoder such that after
draining, the encoder could be used again. We generally suggested
that clients teardown and replace the encoder instance in these
situations. However, for at least some hardware encoders, the cost of
this tear down/replace cycle is very high, which can get in the way of
some use-cases - for example: segmented encoding with nvenc.
To help address that use case, we added support for calling
avcodec_flush_buffers() to nvenc and things worked in practice,
although it was not clearly documented as to whether this should work
or not. There was only one previous example of an encoder implementing
the flush callback (audiotoolboxenc) and it's unclear if that was
intentional or not. However, it was clear that calling
avocdec_flush_buffers() on any other encoder would leave the encoder in
an undefined state, and that's not great.
As part of cleaning this up, this change introduces a formal capability
flag for encoders that support flushing and ensures a flush call is a
no-op for any other encoder. This allows client code to check if it is
meaningful to call flush on an encoder before actually doing it.
I have not attempted to separate the steps taken inside
avcodec_flush_buffers() because it's not doing anything that's wrong
for an encoder. But I did add a sanity check to reject attempts to
flush a frame threaded encoder because I couldn't wrap my head around
whether that code path was actually safe or not. As this combination
doesn't exist today, we'll deal with it if it ever comes up.
5 years ago
. flush = ff_nvenc_encode_flush ,
. priv_data_size = sizeof ( NvencContext ) ,
. priv_class = & nvenc_class ,
. defaults = defaults ,
avcodec: Add explicit capability flag for encoder flushing
Previously, there was no way to flush an encoder such that after
draining, the encoder could be used again. We generally suggested
that clients teardown and replace the encoder instance in these
situations. However, for at least some hardware encoders, the cost of
this tear down/replace cycle is very high, which can get in the way of
some use-cases - for example: segmented encoding with nvenc.
To help address that use case, we added support for calling
avcodec_flush_buffers() to nvenc and things worked in practice,
although it was not clearly documented as to whether this should work
or not. There was only one previous example of an encoder implementing
the flush callback (audiotoolboxenc) and it's unclear if that was
intentional or not. However, it was clear that calling
avocdec_flush_buffers() on any other encoder would leave the encoder in
an undefined state, and that's not great.
As part of cleaning this up, this change introduces a formal capability
flag for encoders that support flushing and ensures a flush call is a
no-op for any other encoder. This allows client code to check if it is
meaningful to call flush on an encoder before actually doing it.
I have not attempted to separate the steps taken inside
avcodec_flush_buffers() because it's not doing anything that's wrong
for an encoder. But I did add a sanity check to reject attempts to
flush a frame threaded encoder because I couldn't wrap my head around
whether that code path was actually safe or not. As this combination
doesn't exist today, we'll deal with it if it ever comes up.
5 years ago
. capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_HARDWARE |
AV_CODEC_CAP_ENCODER_FLUSH ,
. caps_internal = FF_CODEC_CAP_INIT_CLEANUP ,
. pix_fmts = ff_nvenc_pix_fmts ,
. wrapper_name = " nvenc " ,
. hw_configs = ff_nvenc_hw_configs ,
} ;
# endif
/* Add an alias for nvenc_h264 */
# if CONFIG_NVENC_H264_ENCODER
static const AVClass nvenc_h264_class = {
. class_name = " nvenc_h264 " ,
. item_name = av_default_item_name ,
. option = options ,
. version = LIBAVUTIL_VERSION_INT ,
} ;
AVCodec ff_nvenc_h264_encoder = {
. name = " nvenc_h264 " ,
. long_name = NULL_IF_CONFIG_SMALL ( " NVIDIA NVENC H.264 encoder " ) ,
. type = AVMEDIA_TYPE_VIDEO ,
. id = AV_CODEC_ID_H264 ,
. init = nvenc_old_init ,
. send_frame = ff_nvenc_send_frame ,
. receive_packet = ff_nvenc_receive_packet ,
. encode2 = ff_nvenc_encode_frame ,
. close = ff_nvenc_encode_close ,
avcodec: Add explicit capability flag for encoder flushing
Previously, there was no way to flush an encoder such that after
draining, the encoder could be used again. We generally suggested
that clients teardown and replace the encoder instance in these
situations. However, for at least some hardware encoders, the cost of
this tear down/replace cycle is very high, which can get in the way of
some use-cases - for example: segmented encoding with nvenc.
To help address that use case, we added support for calling
avcodec_flush_buffers() to nvenc and things worked in practice,
although it was not clearly documented as to whether this should work
or not. There was only one previous example of an encoder implementing
the flush callback (audiotoolboxenc) and it's unclear if that was
intentional or not. However, it was clear that calling
avocdec_flush_buffers() on any other encoder would leave the encoder in
an undefined state, and that's not great.
As part of cleaning this up, this change introduces a formal capability
flag for encoders that support flushing and ensures a flush call is a
no-op for any other encoder. This allows client code to check if it is
meaningful to call flush on an encoder before actually doing it.
I have not attempted to separate the steps taken inside
avcodec_flush_buffers() because it's not doing anything that's wrong
for an encoder. But I did add a sanity check to reject attempts to
flush a frame threaded encoder because I couldn't wrap my head around
whether that code path was actually safe or not. As this combination
doesn't exist today, we'll deal with it if it ever comes up.
5 years ago
. flush = ff_nvenc_encode_flush ,
. priv_data_size = sizeof ( NvencContext ) ,
. priv_class = & nvenc_h264_class ,
. defaults = defaults ,
avcodec: Add explicit capability flag for encoder flushing
Previously, there was no way to flush an encoder such that after
draining, the encoder could be used again. We generally suggested
that clients teardown and replace the encoder instance in these
situations. However, for at least some hardware encoders, the cost of
this tear down/replace cycle is very high, which can get in the way of
some use-cases - for example: segmented encoding with nvenc.
To help address that use case, we added support for calling
avcodec_flush_buffers() to nvenc and things worked in practice,
although it was not clearly documented as to whether this should work
or not. There was only one previous example of an encoder implementing
the flush callback (audiotoolboxenc) and it's unclear if that was
intentional or not. However, it was clear that calling
avocdec_flush_buffers() on any other encoder would leave the encoder in
an undefined state, and that's not great.
As part of cleaning this up, this change introduces a formal capability
flag for encoders that support flushing and ensures a flush call is a
no-op for any other encoder. This allows client code to check if it is
meaningful to call flush on an encoder before actually doing it.
I have not attempted to separate the steps taken inside
avcodec_flush_buffers() because it's not doing anything that's wrong
for an encoder. But I did add a sanity check to reject attempts to
flush a frame threaded encoder because I couldn't wrap my head around
whether that code path was actually safe or not. As this combination
doesn't exist today, we'll deal with it if it ever comes up.
5 years ago
. capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_HARDWARE |
AV_CODEC_CAP_ENCODER_FLUSH ,
. caps_internal = FF_CODEC_CAP_INIT_CLEANUP ,
. pix_fmts = ff_nvenc_pix_fmts ,
. wrapper_name = " nvenc " ,
. hw_configs = ff_nvenc_hw_configs ,
} ;
# endif
# endif
static const AVClass h264_nvenc_class = {
. class_name = " h264_nvenc " ,
. item_name = av_default_item_name ,
. option = options ,
. version = LIBAVUTIL_VERSION_INT ,
} ;
AVCodec ff_h264_nvenc_encoder = {
. name = " h264_nvenc " ,
. long_name = NULL_IF_CONFIG_SMALL ( " NVIDIA NVENC H.264 encoder " ) ,
. type = AVMEDIA_TYPE_VIDEO ,
. id = AV_CODEC_ID_H264 ,
. init = ff_nvenc_encode_init ,
. send_frame = ff_nvenc_send_frame ,
. receive_packet = ff_nvenc_receive_packet ,
. encode2 = ff_nvenc_encode_frame ,
. close = ff_nvenc_encode_close ,
. flush = ff_nvenc_encode_flush ,
. priv_data_size = sizeof ( NvencContext ) ,
. priv_class = & h264_nvenc_class ,
. defaults = defaults ,
avcodec: Add explicit capability flag for encoder flushing
Previously, there was no way to flush an encoder such that after
draining, the encoder could be used again. We generally suggested
that clients teardown and replace the encoder instance in these
situations. However, for at least some hardware encoders, the cost of
this tear down/replace cycle is very high, which can get in the way of
some use-cases - for example: segmented encoding with nvenc.
To help address that use case, we added support for calling
avcodec_flush_buffers() to nvenc and things worked in practice,
although it was not clearly documented as to whether this should work
or not. There was only one previous example of an encoder implementing
the flush callback (audiotoolboxenc) and it's unclear if that was
intentional or not. However, it was clear that calling
avocdec_flush_buffers() on any other encoder would leave the encoder in
an undefined state, and that's not great.
As part of cleaning this up, this change introduces a formal capability
flag for encoders that support flushing and ensures a flush call is a
no-op for any other encoder. This allows client code to check if it is
meaningful to call flush on an encoder before actually doing it.
I have not attempted to separate the steps taken inside
avcodec_flush_buffers() because it's not doing anything that's wrong
for an encoder. But I did add a sanity check to reject attempts to
flush a frame threaded encoder because I couldn't wrap my head around
whether that code path was actually safe or not. As this combination
doesn't exist today, we'll deal with it if it ever comes up.
5 years ago
. capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_HARDWARE |
AV_CODEC_CAP_ENCODER_FLUSH ,
. caps_internal = FF_CODEC_CAP_INIT_CLEANUP ,
. pix_fmts = ff_nvenc_pix_fmts ,
. wrapper_name = " nvenc " ,
. hw_configs = ff_nvenc_hw_configs ,
} ;
