examples: Add a VA-API encode example.

Supports only raw NV12 input.

Example use:
./vaapi_encode 1920 1080 test.yuv test.h264

Signed-off-by: Jun Zhao <jun.zhao@intel.com>
Signed-off-by: Liu, Kaixuan <kaixuan.liu@intel.com>
Signed-off-by: Mark Thompson <sw@jkqxz.net>

configure

@@ -1522,6 +1522,7 @@ EXAMPLE_LIST="
     scaling_video_example
     transcode_aac_example
     transcoding_example
+    vaapi_encode_example
 "
 
 EXTERNAL_AUTODETECT_LIBRARY_LIST="
@@ -3300,6 +3301,7 @@ resampling_audio_example_deps="avutil swresample"
 scaling_video_example_deps="avutil swscale"
 transcode_aac_example_deps="avcodec avformat swresample"
 transcoding_example_deps="avfilter avcodec avformat avutil"
+vaapi_encode_example_deps="avcodec avutil"
 
 # EXTRALIBS_LIST
 cpu_init_extralibs="pthreads_extralibs"

doc/examples/Makefile

@@ -19,6 +19,7 @@ EXAMPLES-$(CONFIG_RESAMPLING_AUDIO_EXAMPLE)  += resampling_audio
 EXAMPLES-$(CONFIG_SCALING_VIDEO_EXAMPLE)     += scaling_video
 EXAMPLES-$(CONFIG_TRANSCODE_AAC_EXAMPLE)     += transcode_aac
 EXAMPLES-$(CONFIG_TRANSCODING_EXAMPLE)       += transcoding
+EXAMPLES-$(CONFIG_VAAPI_ENCODE_EXAMPLE)      += vaapi_encode
 
 EXAMPLES       := $(EXAMPLES-yes:%=doc/examples/%$(PROGSSUF)$(EXESUF))
 EXAMPLES_G     := $(EXAMPLES-yes:%=doc/examples/%$(PROGSSUF)_g$(EXESUF))

doc/examples/vaapi_encode.c

@@ -0,0 +1,224 @@
+/*
+ * Video Acceleration API (video encoding) encode 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 encoding example.
+ *
+ * @example vaapi_encode.c
+ * This example shows how to do VAAPI-accelerated encoding. now only support NV12
+ * raw file, usage like: vaapi_encode 1920 1080 input.yuv output.h264
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+#include <libavcodec/avcodec.h>
+#include <libavutil/pixdesc.h>
+#include <libavutil/hwcontext.h>
+
+static int width, height;
+static AVBufferRef *hw_device_ctx = NULL;
+
+static int set_hwframe_ctx(AVCodecContext *ctx, AVBufferRef *hw_device_ctx)
+{
+    AVBufferRef *hw_frames_ref;
+    AVHWFramesContext *frames_ctx = NULL;
+    int err = 0;
+
+    if (!(hw_frames_ref = av_hwframe_ctx_alloc(hw_device_ctx))) {
+        fprintf(stderr, "Failed to create VAAPI frame context.\n");
+        return -1;
+    }
+    frames_ctx = (AVHWFramesContext *)(hw_frames_ref->data);
+    frames_ctx->format    = AV_PIX_FMT_VAAPI;
+    frames_ctx->sw_format = AV_PIX_FMT_NV12;
+    frames_ctx->width     = width;
+    frames_ctx->height    = height;
+    frames_ctx->initial_pool_size = 20;
+    if ((err = av_hwframe_ctx_init(hw_frames_ref)) < 0) {
+        fprintf(stderr, "Failed to initialize VAAPI frame context."
+                "Error code: %s\n",av_err2str(err));
+        return err;
+    }
+    ctx->hw_frames_ctx = av_buffer_ref(hw_frames_ref);
+    if (!ctx->hw_frames_ctx)
+        err = AVERROR(ENOMEM);
+
+    av_buffer_unref(&hw_frames_ref);
+    return err;
+}
+
+static int encode_write(AVCodecContext *avctx, AVFrame *frame, FILE *fout)
+{
+    int ret = 0;
+    AVPacket enc_pkt;
+
+    av_init_packet(&enc_pkt);
+    enc_pkt.data = NULL;
+    enc_pkt.size = 0;
+
+    if ((ret = avcodec_send_frame(avctx, frame)) < 0) {
+        fprintf(stderr, "Error code: %s\n", av_err2str(ret));
+        goto end;
+    }
+    while (1) {
+        ret = avcodec_receive_packet(avctx, &enc_pkt);
+        if (ret)
+            break;
+
+        enc_pkt.stream_index = 0;
+        ret = fwrite(enc_pkt.data, enc_pkt.size, 1, fout);
+        av_packet_unref(&enc_pkt);
+    }
+
+end:
+    ret = ((ret == AVERROR(EAGAIN)) ? 0 : -1);
+    return ret;
+}
+
+int main(int argc, char *argv[])
+{
+    int size, err;
+    FILE *fin = NULL, *fout = NULL;
+    AVFrame *sw_frame = NULL, *hw_frame = NULL;
+    AVCodecContext *avctx = NULL;
+    AVCodec *codec = NULL;
+    const char *enc_name = "h264_vaapi";
+
+    if (argc < 5) {
+        fprintf(stderr, "Usage: %s <width> <height> <input file> <output file>\n", argv[0]);
+        return -1;
+    }
+
+    width  = atoi(argv[1]);
+    height = atoi(argv[2]);
+    size   = width * height;
+
+    if (!(fin = fopen(argv[3], "r"))) {
+        fprintf(stderr, "Fail to open input file : %s\n", strerror(errno));
+        return -1;
+    }
+    if (!(fout = fopen(argv[4], "w+b"))) {
+        fprintf(stderr, "Fail to open output file : %s\n", strerror(errno));
+        err = -1;
+        goto close;
+    }
+
+    avcodec_register_all();
+
+    err = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI,
+                                 NULL, NULL, 0);
+    if (err < 0) {
+        fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(err));
+        goto close;
+    }
+
+    if (!(codec = avcodec_find_encoder_by_name(enc_name))) {
+        fprintf(stderr, "Could not find encoder.\n");
+        err = -1;
+        goto close;
+    }
+
+    if (!(avctx = avcodec_alloc_context3(codec))) {
+        err = AVERROR(ENOMEM);
+        goto close;
+    }
+
+    avctx->width     = width;
+    avctx->height    = height;
+    avctx->time_base = (AVRational){1, 25};
+    avctx->framerate = (AVRational){25, 1};
+    avctx->sample_aspect_ratio = (AVRational){1, 1};
+    avctx->pix_fmt   = AV_PIX_FMT_VAAPI;
+
+    /* set hw_frames_ctx for encoder's AVCodecContext */
+    if ((err = set_hwframe_ctx(avctx, hw_device_ctx)) < 0) {
+        fprintf(stderr, "Failed to set hwframe context.\n");
+        goto close;
+    }
+
+    if ((err = avcodec_open2(avctx, codec, NULL)) < 0) {
+        fprintf(stderr, "Cannot open video encoder codec. Error code: %s\n", av_err2str(err));
+        goto close;
+    }
+
+    while (1) {
+        if (!(sw_frame = av_frame_alloc())) {
+            err = AVERROR(ENOMEM);
+            goto close;
+        }
+        /* read data into software frame, and transfer them into hw frame */
+        sw_frame->width  = width;
+        sw_frame->height = height;
+        sw_frame->format = AV_PIX_FMT_NV12;
+        if ((err = av_frame_get_buffer(sw_frame, 32)) < 0)
+            goto close;
+        if ((err = fread((uint8_t*)(sw_frame->data[0]), size, 1, fin)) <= 0)
+            break;
+        if ((err = fread((uint8_t*)(sw_frame->data[1]), size/2, 1, fin)) <= 0)
+            break;
+
+        if (!(hw_frame = av_frame_alloc())) {
+            err = AVERROR(ENOMEM);
+            goto close;
+        }
+        if ((err = av_hwframe_get_buffer(avctx->hw_frames_ctx, hw_frame, 0)) < 0) {
+            fprintf(stderr, "Error code: %s.\n", av_err2str(err));
+            goto close;
+        }
+        if (!hw_frame->hw_frames_ctx) {
+            err = AVERROR(ENOMEM);
+            goto close;
+        }
+        if ((err = av_hwframe_transfer_data(hw_frame, sw_frame, 0)) < 0) {
+            fprintf(stderr, "Error while transferring frame data to surface."
+                    "Error code: %s.\n", av_err2str(err));
+            goto close;
+        }
+
+        if ((err = (encode_write(avctx, hw_frame, fout))) < 0) {
+            fprintf(stderr, "Failed to encode.\n");
+            goto close;
+        }
+        av_frame_free(&hw_frame);
+        av_frame_free(&sw_frame);
+    }
+
+    /* flush encoder */
+    err = encode_write(avctx, NULL, fout);
+    if (err == AVERROR_EOF)
+        err = 0;
+
+close:
+    if (fin)
+        fclose(fin);
+    if (fout)
+        fclose(fout);
+    av_frame_free(&sw_frame);
+    av_frame_free(&hw_frame);
+    if (avctx)
+        avcodec_free_context(&avctx);
+    av_buffer_unref(&hw_device_ctx);
+
+    return err;
+}