From f033ba470fbab1ff6838666d4d86411effa97b27 Mon Sep 17 00:00:00 2001 From: Mark Thompson Date: Sun, 29 Jan 2017 14:11:03 +0000 Subject: [PATCH] vaapi_encode: Support VBR mode This includes a backward-compatibility hack to choose CBR anyway on old drivers which have no CBR support, so that existing programs will continue to work their options now map to VBR. --- libavcodec/vaapi_encode.c | 42 ++++++++++++++++++++++++++++++++++----- 1 file changed, 37 insertions(+), 5 deletions(-) diff --git a/libavcodec/vaapi_encode.c b/libavcodec/vaapi_encode.c index 9895c5a311..e9aa48606a 100644 --- a/libavcodec/vaapi_encode.c +++ b/libavcodec/vaapi_encode.c @@ -1034,6 +1034,19 @@ static av_cold int vaapi_encode_config_attributes(AVCodecContext *avctx) }; break; case VAConfigAttribRateControl: + // Hack for backward compatibility: CBR was the only + // usable RC mode for a long time, so old drivers will + // only have it. Normal default options may now choose + // VBR and then fail, however, so override it here with + // CBR if that is the only supported mode. + if (ctx->va_rc_mode == VA_RC_VBR && + !(attr[i].value & VA_RC_VBR) && + (attr[i].value & VA_RC_CBR)) { + av_log(avctx, AV_LOG_WARNING, "VBR rate control is " + "not supported with this driver version; " + "using CBR instead.\n"); + ctx->va_rc_mode = VA_RC_CBR; + } if (!(ctx->va_rc_mode & attr[i].value)) { av_log(avctx, AV_LOG_ERROR, "Rate control mode %#x " "is not supported (mask: %#x).\n", @@ -1098,6 +1111,9 @@ fail: static av_cold int vaapi_encode_init_rate_control(AVCodecContext *avctx) { VAAPIEncodeContext *ctx = avctx->priv_data; + int rc_bits_per_second; + int rc_target_percentage; + int rc_window_size; int hrd_buffer_size; int hrd_initial_buffer_fullness; @@ -1110,13 +1126,29 @@ static av_cold int vaapi_encode_init_rate_control(AVCodecContext *avctx) else hrd_initial_buffer_fullness = hrd_buffer_size * 3 / 4; + if (ctx->va_rc_mode == VA_RC_CBR) { + rc_bits_per_second = avctx->bit_rate; + rc_target_percentage = 100; + rc_window_size = 1000; + } else { + if (avctx->rc_max_rate < avctx->bit_rate) { + // Max rate is unset or invalid, just use the normal bitrate. + rc_bits_per_second = avctx->bit_rate; + rc_target_percentage = 100; + } else { + rc_bits_per_second = avctx->rc_max_rate; + rc_target_percentage = (avctx->bit_rate * 100) / rc_bits_per_second; + } + rc_window_size = (hrd_buffer_size * 1000) / avctx->bit_rate; + } + ctx->rc_params.misc.type = VAEncMiscParameterTypeRateControl; ctx->rc_params.rc = (VAEncMiscParameterRateControl) { - .bits_per_second = avctx->bit_rate, - .target_percentage = 66, - .window_size = 1000, - .initial_qp = (avctx->qmax >= 0 ? avctx->qmax : 40), - .min_qp = (avctx->qmin >= 0 ? avctx->qmin : 18), + .bits_per_second = rc_bits_per_second, + .target_percentage = rc_target_percentage, + .window_size = rc_window_size, + .initial_qp = 0, + .min_qp = (avctx->qmin > 0 ? avctx->qmin : 0), .basic_unit_size = 0, }; ctx->global_params[ctx->nb_global_params] =