[FFmpeg-devel] [PATCH] examples/vaapi_dec: Add a VA-API hwaccel decoding example
Jun Zhao
mypopydev at gmail.com
Tue Mar 21 06:45:26 EET 2017
From 6b56c541ed7dd271ad0aa6eb6412a8427f009525 Mon Sep 17 00:00:00 2001
From: Jun Zhao <jun.zhao at intel.com>
Date: Tue, 21 Mar 2017 11:04:41 +0800
Subject: [PATCH] examples/vaapi_dec: Add a VA-API hwaccel decoding example.
Add a VA-API hwaccel decoding example.
Signed-off-by: Liu, Kaixuan <kaixuan.liu at intel.com>
Signed-off-by: Jun Zhao <jun.zhao at intel.com>
---
doc/examples/vaapi_dec.c | 346 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 346 insertions(+)
create mode 100644 doc/examples/vaapi_dec.c
diff --git a/doc/examples/vaapi_dec.c b/doc/examples/vaapi_dec.c
new file mode 100644
index 0000000..f975d86
--- /dev/null
+++ b/doc/examples/vaapi_dec.c
@@ -0,0 +1,346 @@
+/*
+ * Video Acceleration API (video decoding) decode sample
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * Intel VAAPI-accelerated decoding example.
+ *
+ * @example vaapi_dec.c
+ * This example shows how to do VAAPI-accelerated decoding with output
+ * frames from the VAAPI video surfaces.
+ */
+
+#include <stdio.h>
+#include <libavcodec/avcodec.h>
+#include <libavcodec/vaapi.h>
+#include <libavformat/avformat.h>
+#include <libswscale/swscale.h>
+#include <libavutil/pixdesc.h>
+#include <libavutil/hwcontext.h>
+#include <libavutil/opt.h>
+#include <libavutil/hwcontext_vaapi.h>
+#include <libavutil/avassert.h>
+#include <va/va.h>
+#include <va/va_x11.h>
+#include <va/va_drm.h>
+
+#define DEFAULT_SURFACES 20
+static enum AVPixelFormat decode_format = AV_PIX_FMT_NV12;
+static enum AVPixelFormat output_format = AV_PIX_FMT_NV12; /* default output format nv12 */
+static AVBufferRef *frames_ref = NULL;
+static AVBufferRef *device_ref = NULL;
+FILE *output_file = NULL;
+
+void decoder_uninit_vaapi(AVCodecContext *avctx, AVVAAPIDeviceContext *hwctx)
+{
+ if (hwctx) {
+ av_buffer_unref(&frames_ref);
+ av_buffer_unref(&device_ref);
+ }
+ return;
+}
+
+int decoder_init_vaapi(AVCodecContext *ctx)
+{
+ AVBufferRef *hw_device_ctx = NULL;
+ AVHWFramesContext *frames;
+ int err = 0;
+ char *dev_name = "/dev/dri/renderD128";
+ AVBufferRef *device_ref = NULL;
+ AVHWDeviceContext *device = NULL;
+ AVVAAPIDeviceContext *hwctx = NULL;
+
+ if ((err = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI,
+ dev_name, NULL, 0)) < 0) {
+ fprintf(stderr, "Failed to create a VAAPI device.\n");
+ return err;
+ }
+
+ device_ref = av_buffer_ref(hw_device_ctx);
+ device = (AVHWDeviceContext *)device_ref->data;
+ hwctx = (AVVAAPIDeviceContext *)device->hwctx;
+
+ ctx->pix_fmt = output_format;
+ if (!(frames_ref = av_hwframe_ctx_alloc(device_ref))) {
+ fprintf(stderr, "Failed to create VAAPI frame context.\n");
+ err = AVERROR(ENOMEM);
+ goto fail;
+ }
+ frames = (AVHWFramesContext *)frames_ref->data;
+ frames->format = AV_PIX_FMT_VAAPI;
+ frames->sw_format = decode_format;
+ frames->width = ctx->coded_width;
+ frames->height = ctx->coded_height;
+ frames->initial_pool_size = DEFAULT_SURFACES;
+ if ((err = av_hwframe_ctx_init(frames_ref)) < 0) {
+ fprintf(stderr, "Failed to initialize VAAPI frame.\n");
+ goto fail;
+ }
+
+ ctx->hw_frames_ctx = av_buffer_ref(frames_ref);
+ if (!ctx->hw_frames_ctx) {
+ err = AVERROR(ENOMEM);
+ fprintf(stderr, "Failed to ref VAAPI frame.\n");
+ goto fail;
+ }
+
+fail:
+ if (err < 0)
+ decoder_uninit_vaapi(ctx, hwctx);
+ return err;
+}
+
+static enum AVPixelFormat get_hw_vaapi_format(AVCodecContext *ctx,
+ const enum AVPixelFormat *pix_fmts)
+{
+ const enum AVPixelFormat *p;
+ int ret;
+
+ for (p = pix_fmts; *p != -1; p++) {
+ const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(*p);
+ if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
+ break;
+
+ if (!(strstr(desc->name, "vaapi")))
+ continue;
+
+ if ((ret = decoder_init_vaapi(ctx)) < 0) {
+ fprintf(stderr, "hwaccel for decoder(VAAPI) cannot be initialized.\n");
+ return AV_PIX_FMT_NONE;
+ }
+ break;
+ }
+ return *p;
+}
+
+static int get_hw_vaapi_buffer(AVCodecContext *ctx, AVFrame *frame, int flags)
+{
+ int err;
+ if ((err = av_hwframe_get_buffer(frames_ref, frame, 0)) < 0)
+ av_log(NULL, AV_LOG_ERROR, "Failed to allocate decoder surface.\n");
+
+ return err;
+}
+
+int retrieve_data(AVFrame *input)
+{
+ AVFrame *output = 0;
+ int err;
+ av_assert0(input->format == AV_PIX_FMT_VAAPI);
+
+ if (output_format == AV_PIX_FMT_VAAPI)
+ return 0;
+
+ if (!(output = av_frame_alloc()))
+ return AVERROR(ENOMEM);
+ output->format = output_format;
+ if ((err = av_hwframe_transfer_data(output, input, 0)) < 0) {
+ fprintf(stderr, "Failed to transfer data to output frame: %d.\n", err);
+ goto fail;
+ }
+
+ if ((err = av_frame_copy_props(output, input)) < 0) {
+ av_frame_unref(output);
+ goto fail;
+ }
+
+ av_frame_unref(input);
+ av_frame_move_ref(input, output);
+ av_frame_free(&output);
+ return 0;
+
+fail:
+ av_frame_free(&output);
+ return err;
+}
+
+int write_frame(AVFrame *frame)
+{
+ int idx, size;
+ int width = frame->width;
+ int height = frame->height;
+
+ av_assert0(frame && frame->data[0] && output_file);
+
+ for (idx = 0; idx < height; idx++) {
+ if ((size = fwrite(frame->data[0] + idx*frame->linesize[0],
+ 1, width, output_file)) < 0) {
+ fprintf(stderr, "Dump Y to file error.\n");
+ return -1;
+ }
+ }
+
+ height >>= 1;
+ for (idx = 0; idx < height; idx++) {
+ if ((size = fwrite(frame->data[1] + idx*frame->linesize[1],
+ 1, width, output_file)) < 0) {
+ fprintf(stderr, "Dump UV to file error.\n");
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+int decode_write(AVCodecContext *avctx, AVPacket packet, int flush)
+{
+ AVFrame *frame = NULL;
+ int ret = 0, got_frame = 0;
+
+ if (!(frame = av_frame_alloc()))
+ return AVERROR(ENOMEM);
+
+ if ((ret = avcodec_decode_video2(avctx, frame, &got_frame, &packet)) < 0) {
+ fprintf(stderr, "Error during decoding\n");
+ goto fail;
+ }
+
+ if (got_frame) {
+ if (AV_PIX_FMT_VAAPI == frame->format) {
+ /* retrieve data from GPU to CPU */
+ if ((ret = retrieve_data(frame)) < 0)
+ goto fail;
+
+ if ((ret = write_frame(frame)) < 0)
+ goto fail;
+ }
+ } else if (flush == 1) {
+ ret = -1;
+ }
+
+fail:
+ av_frame_free(&frame);
+ return ret;
+}
+
+/* flush the decoder */
+int flush(AVCodecContext *avctx)
+{
+ AVPacket packet;
+ int ret = 0;
+
+ av_init_packet(&packet);
+ packet.data = NULL;
+ packet.size = 0;
+
+ while (1) {
+ if ((ret = decode_write(avctx, packet, 1)) < 0)
+ break;
+ }
+ av_packet_unref(&packet);
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ AVFormatContext *input_ctx = NULL;
+ int i,video_stream,ret;
+ AVCodecContext *decoder_ctx = NULL;
+ AVCodec *decoder = NULL;
+ AVPacket packet;
+
+ if (argc < 3) {
+ fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
+ return -1;
+ }
+
+ av_register_all();
+
+ /* open the input file */
+ if (avformat_open_input(&input_ctx, argv[1], NULL, NULL) != 0) {
+ fprintf(stderr, "Cannot open input file '%s'\n", argv[1]);
+ return -1;
+ }
+
+ if (avformat_find_stream_info(input_ctx, NULL) < 0) {
+ fprintf(stderr, "Couldn't find input stream information.\n");
+ return -1;
+ }
+
+ /* find the video stream information */
+ video_stream = -1;
+ for (i = 0; i < input_ctx->nb_streams; i++) {
+ AVStream *st = input_ctx->streams[i];
+ if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
+ /* NOTE: just handle the first video stream */
+ video_stream = i;
+ break;
+ }
+ }
+
+ if (video_stream == -1) {
+ fprintf(stderr, "No find a video stream in the input file.\n");
+ return -1;
+ }
+
+ /* initialize the video decoder */
+ if (!(decoder = avcodec_find_decoder(input_ctx->streams[video_stream]->codecpar->codec_id))) {
+ fprintf(stderr, "Could not find input codec\n");
+ avformat_close_input(&input_ctx);
+ return -1;
+ }
+
+ if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
+ return AVERROR(ENOMEM);
+
+ if (avcodec_parameters_to_context(decoder_ctx,
+ input_ctx->streams[video_stream]->codecpar) < 0) {
+ avcodec_free_context(&decoder_ctx);
+ avformat_close_input(&input_ctx);
+ return -1;
+ }
+
+ decoder_ctx->get_format = get_hw_vaapi_format;
+ decoder_ctx->get_buffer2 = get_hw_vaapi_buffer;
+ av_opt_set_int(decoder_ctx, "refcounted_frames", 1, 0);
+
+ if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0) {
+ fprintf(stderr, "Failed to open codec for stream #%u\n", i);
+ return ret;
+ }
+
+ /* open the output file to dump YUV */
+ output_file = fopen(argv[2], "w+");
+
+ /* actual decoding and dump the YUV data */
+ while (av_read_frame(input_ctx, &packet) >= 0) {
+ if (video_stream == packet.stream_index)
+ ret = decode_write(decoder_ctx, packet, 0);
+ av_packet_unref(&packet);
+
+ if (ret < 0)
+ break;
+ }
+
+ /* flush the decoder */
+ flush(decoder_ctx);
+
+ if (output_file)
+ fclose(output_file);
+ avcodec_free_context(&decoder_ctx);
+ avformat_close_input(&input_ctx);
+
+ av_buffer_unref(&frames_ref);
+ av_buffer_unref(&device_ref);
+
+ return ret;
+}
+
--
2.9.3
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