h264dec: add a NVDEC hwaccel

Some parts of the code are based on a patch by
Timo Rothenpieler <timo@rothenpieler.org>

Merges Libav commit b9129ec4668c511e0a79e25c6f25d748cee172c9.

Due to the name clash with our cuvid decoder, rename it to nvdec.

This commit also changes the Libav code to dynamic loading of the
cuda/cuvid libraries.

Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>

1 files changed, 431 insertions, 0 deletions

diff --git a/libavcodec/nvdec.c b/libavcodec/nvdec.c
new file mode 100644
index 0000000000..9ca9faa378
--- /dev/null
+++ b/libavcodec/nvdec.c
@@ -0,0 +1,431 @@
+/*
+ * HW decode acceleration through NVDEC
+ *
+ * Copyright (c) 2016 Anton Khirnov
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+
+#include "libavutil/common.h"
+#include "libavutil/error.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/hwcontext_cuda_internal.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/pixfmt.h"
+
+#include "avcodec.h"
+#include "decode.h"
+#include "nvdec.h"
+#include "internal.h"
+
+typedef struct NVDECDecoder {
+    CUvideodecoder decoder;
+
+    AVBufferRef *hw_device_ref;
+    CUcontext    cuda_ctx;
+
+    CudaFunctions *cudl;
+    CuvidFunctions *cvdl;
+} NVDECDecoder;
+
+typedef struct NVDECFramePool {
+    unsigned int dpb_size;
+    unsigned int nb_allocated;
+} NVDECFramePool;
+
+static int map_avcodec_id(enum AVCodecID id)
+{
+    switch (id) {
+    case AV_CODEC_ID_H264: return cudaVideoCodec_H264;
+    }
+    return -1;
+}
+
+static int map_chroma_format(enum AVPixelFormat pix_fmt)
+{
+    int shift_h = 0, shift_v = 0;
+
+    av_pix_fmt_get_chroma_sub_sample(pix_fmt, &shift_h, &shift_v);
+
+    if (shift_h == 1 && shift_v == 1)
+        return cudaVideoChromaFormat_420;
+    else if (shift_h == 1 && shift_v == 0)
+        return cudaVideoChromaFormat_422;
+    else if (shift_h == 0 && shift_v == 0)
+        return cudaVideoChromaFormat_444;
+
+    return -1;
+}
+
+static void nvdec_decoder_free(void *opaque, uint8_t *data)
+{
+    NVDECDecoder *decoder = (NVDECDecoder*)data;
+
+    if (decoder->decoder)
+        decoder->cvdl->cuvidDestroyDecoder(decoder->decoder);
+
+    av_buffer_unref(&decoder->hw_device_ref);
+
+    cuvid_free_functions(&decoder->cvdl);
+
+    av_freep(&decoder);
+}
+
+static int nvdec_decoder_create(AVBufferRef **out, AVBufferRef *hw_device_ref,
+                                CUVIDDECODECREATEINFO *params, void *logctx)
+{
+    AVHWDeviceContext  *hw_device_ctx = (AVHWDeviceContext*)hw_device_ref->data;
+    AVCUDADeviceContext *device_hwctx = hw_device_ctx->hwctx;
+
+    AVBufferRef *decoder_ref;
+    NVDECDecoder *decoder;
+
+    CUcontext dummy;
+    CUresult err;
+    int ret;
+
+    decoder = av_mallocz(sizeof(*decoder));
+    if (!decoder)
+        return AVERROR(ENOMEM);
+
+    decoder_ref = av_buffer_create((uint8_t*)decoder, sizeof(*decoder),
+                                   nvdec_decoder_free, NULL, AV_BUFFER_FLAG_READONLY);
+    if (!decoder_ref) {
+        av_freep(&decoder);
+        return AVERROR(ENOMEM);
+    }
+
+    decoder->hw_device_ref = av_buffer_ref(hw_device_ref);
+    if (!decoder->hw_device_ref) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+    decoder->cuda_ctx = device_hwctx->cuda_ctx;
+    decoder->cudl = device_hwctx->internal->cuda_dl;
+
+    ret = cuvid_load_functions(&decoder->cvdl);
+    if (ret < 0) {
+        av_log(logctx, AV_LOG_ERROR, "Failed loading nvcuvid.\n");
+        goto fail;
+    }
+
+    err = decoder->cudl->cuCtxPushCurrent(decoder->cuda_ctx);
+    if (err != CUDA_SUCCESS) {
+        ret = AVERROR_UNKNOWN;
+        goto fail;
+    }
+
+    err = decoder->cvdl->cuvidCreateDecoder(&decoder->decoder, params);
+
+    decoder->cudl->cuCtxPopCurrent(&dummy);
+
+    if (err != CUDA_SUCCESS) {
+        av_log(logctx, AV_LOG_ERROR, "Error creating a NVDEC decoder: %d\n", err);
+        ret = AVERROR_UNKNOWN;
+        goto fail;
+    }
+
+    *out = decoder_ref;
+
+    return 0;
+fail:
+    av_buffer_unref(&decoder_ref);
+    return ret;
+}
+
+static AVBufferRef *nvdec_decoder_frame_alloc(void *opaque, int size)
+{
+    NVDECFramePool *pool = opaque;
+    AVBufferRef *ret;
+
+    if (pool->nb_allocated >= pool->dpb_size)
+        return NULL;
+
+    ret = av_buffer_alloc(sizeof(unsigned int));
+    if (!ret)
+        return NULL;
+
+    *(unsigned int*)ret->data = pool->nb_allocated++;
+
+    return ret;
+}
+
+int ff_nvdec_decode_uninit(AVCodecContext *avctx)
+{
+    NVDECContext *ctx = avctx->internal->hwaccel_priv_data;
+
+    av_freep(&ctx->bitstream);
+    ctx->bitstream_len       = 0;
+    ctx->bitstream_allocated = 0;
+
+    av_freep(&ctx->slice_offsets);
+    ctx->nb_slices               = 0;
+    ctx->slice_offsets_allocated = 0;
+
+    av_buffer_unref(&ctx->decoder_ref);
+    av_buffer_pool_uninit(&ctx->decoder_pool);
+
+    return 0;
+}
+
+int ff_nvdec_decode_init(AVCodecContext *avctx, unsigned int dpb_size)
+{
+    NVDECContext *ctx = avctx->internal->hwaccel_priv_data;
+
+    NVDECFramePool      *pool;
+    AVHWFramesContext   *frames_ctx;
+    const AVPixFmtDescriptor *sw_desc;
+
+    CUVIDDECODECREATEINFO params = { 0 };
+
+    int cuvid_codec_type, cuvid_chroma_format;
+    int ret = 0;
+
+    sw_desc = av_pix_fmt_desc_get(avctx->sw_pix_fmt);
+    if (!sw_desc)
+        return AVERROR_BUG;
+
+    cuvid_codec_type = map_avcodec_id(avctx->codec_id);
+    if (cuvid_codec_type < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Unsupported codec ID\n");
+        return AVERROR_BUG;
+    }
+
+    cuvid_chroma_format = map_chroma_format(avctx->sw_pix_fmt);
+    if (cuvid_chroma_format < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Unsupported chroma format\n");
+        return AVERROR(ENOSYS);
+    }
+
+    if (avctx->thread_type & FF_THREAD_FRAME)
+        dpb_size += avctx->thread_count;
+
+    if (!avctx->hw_frames_ctx) {
+        AVHWFramesContext *frames_ctx;
+
+        if (!avctx->hw_device_ctx) {
+            av_log(avctx, AV_LOG_ERROR, "A hardware device or frames context "
+                   "is required for CUVID decoding.\n");
+            return AVERROR(EINVAL);
+        }
+
+        avctx->hw_frames_ctx = av_hwframe_ctx_alloc(avctx->hw_device_ctx);
+        if (!avctx->hw_frames_ctx)
+            return AVERROR(ENOMEM);
+        frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+
+        frames_ctx->format            = AV_PIX_FMT_CUDA;
+        frames_ctx->width             = avctx->coded_width;
+        frames_ctx->height            = avctx->coded_height;
+        frames_ctx->sw_format         = AV_PIX_FMT_NV12;
+        frames_ctx->sw_format         = sw_desc->comp[0].depth > 8 ?
+                                        AV_PIX_FMT_P010 : AV_PIX_FMT_NV12;
+        frames_ctx->initial_pool_size = dpb_size;
+
+        ret = av_hwframe_ctx_init(avctx->hw_frames_ctx);
+        if (ret < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Error initializing internal frames context\n");
+            return ret;
+        }
+    }
+    frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+
+    params.ulWidth             = avctx->coded_width;
+    params.ulHeight            = avctx->coded_height;
+    params.ulTargetWidth       = avctx->coded_width;
+    params.ulTargetHeight      = avctx->coded_height;
+    params.bitDepthMinus8      = sw_desc->comp[0].depth - 8;
+    params.OutputFormat        = params.bitDepthMinus8 ?
+                                 cudaVideoSurfaceFormat_P016 : cudaVideoSurfaceFormat_NV12;
+    params.CodecType           = cuvid_codec_type;
+    params.ChromaFormat        = cuvid_chroma_format;
+    params.ulNumDecodeSurfaces = dpb_size;
+    params.ulNumOutputSurfaces = 1;
+
+    ret = nvdec_decoder_create(&ctx->decoder_ref, frames_ctx->device_ref, &params, avctx);
+    if (ret < 0)
+        return ret;
+
+    pool = av_mallocz(sizeof(*pool));
+    if (!pool) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+    pool->dpb_size = dpb_size;
+
+    ctx->decoder_pool = av_buffer_pool_init2(sizeof(int), pool,
+                                             nvdec_decoder_frame_alloc, av_free);
+    if (!ctx->decoder_pool) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+
+    return 0;
+fail:
+    ff_nvdec_decode_uninit(avctx);
+    return ret;
+}
+
+static void nvdec_fdd_priv_free(void *priv)
+{
+    NVDECFrame *cf = priv;
+
+    if (!cf)
+        return;
+
+    av_buffer_unref(&cf->idx_ref);
+    av_buffer_unref(&cf->decoder_ref);
+
+    av_freep(&priv);
+}
+
+static int nvdec_retrieve_data(void *logctx, AVFrame *frame)
+{
+    FrameDecodeData  *fdd = (FrameDecodeData*)frame->private_ref->data;
+    NVDECFrame        *cf = (NVDECFrame*)fdd->hwaccel_priv;
+    NVDECDecoder *decoder = (NVDECDecoder*)cf->decoder_ref->data;
+
+    CUVIDPROCPARAMS vpp = { .progressive_frame = 1 };
+
+    CUresult err;
+    CUcontext dummy;
+    CUdeviceptr devptr;
+
+    unsigned int pitch, i;
+    unsigned int offset = 0;
+    int ret = 0;
+
+    err = decoder->cudl->cuCtxPushCurrent(decoder->cuda_ctx);
+    if (err != CUDA_SUCCESS)
+        return AVERROR_UNKNOWN;
+
+    err = decoder->cvdl->cuvidMapVideoFrame(decoder->decoder, cf->idx, &devptr,
+                                            &pitch, &vpp);
+    if (err != CUDA_SUCCESS) {
+        av_log(logctx, AV_LOG_ERROR, "Error mapping a picture with CUVID: %d\n",
+               err);
+        ret = AVERROR_UNKNOWN;
+        goto finish;
+    }
+
+    for (i = 0; frame->data[i]; i++) {
+        CUDA_MEMCPY2D cpy = {
+            .srcMemoryType = CU_MEMORYTYPE_DEVICE,
+            .dstMemoryType = CU_MEMORYTYPE_DEVICE,
+            .srcDevice     = devptr,
+            .dstDevice     = (CUdeviceptr)frame->data[i],
+            .srcPitch      = pitch,
+            .dstPitch      = frame->linesize[i],
+            .srcY          = offset,
+            .WidthInBytes  = FFMIN(pitch, frame->linesize[i]),
+            .Height        = frame->height >> (i ? 1 : 0),
+        };
+
+        err = decoder->cudl->cuMemcpy2D(&cpy);
+        if (err != CUDA_SUCCESS) {
+            av_log(logctx, AV_LOG_ERROR, "Error copying decoded frame: %d\n",
+                   err);
+            ret = AVERROR_UNKNOWN;
+            goto copy_fail;
+        }
+
+        offset += cpy.Height;
+    }
+
+copy_fail:
+    decoder->cvdl->cuvidUnmapVideoFrame(decoder->decoder, devptr);
+
+finish:
+    decoder->cudl->cuCtxPopCurrent(&dummy);
+    return ret;
+}
+
+int ff_nvdec_start_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    NVDECContext *ctx = avctx->internal->hwaccel_priv_data;
+    FrameDecodeData *fdd = (FrameDecodeData*)frame->private_ref->data;
+    NVDECFrame *cf = NULL;
+    int ret;
+
+    ctx->bitstream_len = 0;
+    ctx->nb_slices     = 0;
+
+    if (fdd->hwaccel_priv)
+        return 0;
+
+    cf = av_mallocz(sizeof(*cf));
+    if (!cf)
+        return AVERROR(ENOMEM);
+
+    cf->decoder_ref = av_buffer_ref(ctx->decoder_ref);
+    if (!cf->decoder_ref)
+        goto fail;
+
+    cf->idx_ref = av_buffer_pool_get(ctx->decoder_pool);
+    if (!cf->idx_ref) {
+        av_log(avctx, AV_LOG_ERROR, "No decoder surfaces left\n");
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+    cf->idx = *(unsigned int*)cf->idx_ref->data;
+
+    fdd->hwaccel_priv      = cf;
+    fdd->hwaccel_priv_free = nvdec_fdd_priv_free;
+    fdd->post_process      = nvdec_retrieve_data;
+
+    return 0;
+fail:
+    nvdec_fdd_priv_free(cf);
+    return ret;
+
+}
+
+int ff_nvdec_end_frame(AVCodecContext *avctx)
+{
+    NVDECContext     *ctx = avctx->internal->hwaccel_priv_data;
+    NVDECDecoder *decoder = (NVDECDecoder*)ctx->decoder_ref->data;
+    CUVIDPICPARAMS    *pp = &ctx->pic_params;
+
+    CUresult err;
+    CUcontext dummy;
+
+    int ret = 0;
+
+    pp->nBitstreamDataLen = ctx->bitstream_len;
+    pp->pBitstreamData    = ctx->bitstream;
+    pp->nNumSlices        = ctx->nb_slices;
+    pp->pSliceDataOffsets = ctx->slice_offsets;
+
+    err = decoder->cudl->cuCtxPushCurrent(decoder->cuda_ctx);
+    if (err != CUDA_SUCCESS)
+        return AVERROR_UNKNOWN;
+
+    err = decoder->cvdl->cuvidDecodePicture(decoder->decoder, &ctx->pic_params);
+    if (err != CUDA_SUCCESS) {
+        av_log(avctx, AV_LOG_ERROR, "Error decoding a picture with NVDEC: %d\n",
+               err);
+        ret = AVERROR_UNKNOWN;
+        goto finish;
+    }
+
+finish:
+    decoder->cudl->cuCtxPopCurrent(&dummy);
+
+    return ret;
+}