lavd: add xv output device

Based on the work of Jeff Moguillansky <Jeff.Moguillansky@am.sony.com>.

See thread:
Subject: [FFmpeg-devel] x11 output device for libavdevice
Date: Wed, 10 Apr 2013 23:10:47 +0000

1 files changed, 217 insertions, 0 deletions

diff --git a/libavdevice/xv.c b/libavdevice/xv.c
new file mode 100644
index 0000000..670c4de
--- /dev/null
+++ b/libavdevice/xv.c
@@ -0,0 +1,217 @@
+/*
+ * Copyright (c) 2013 Jeff Moguillansky
+ *
+ * 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
+ * XVideo output device
+ *
+ * TODO:
+ * - add support to more formats
+ * - add support to window id specification
+ */
+
+#include <X11/Xlib.h>
+#include <X11/extensions/Xv.h>
+#include <X11/extensions/Xvlib.h>
+#include <X11/extensions/XShm.h>
+#include <sys/shm.h>
+
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+#include "avdevice.h"
+
+typedef struct {
+    AVClass *class;
+    GC gc;
+
+    Window window;
+    char *window_title;
+    int window_width, window_height;
+    int window_x, window_y;
+
+    Display* display;
+    char *display_name;
+
+    XvImage* yuv_image;
+    int image_width, image_height;
+    XShmSegmentInfo yuv_shminfo;
+    int xv_port;
+} XVContext;
+
+static int xv_write_header(AVFormatContext *s)
+{
+    XVContext *xv = s->priv_data;
+    unsigned int num_adaptors;
+    XvAdaptorInfo *ai;
+    XvImageFormatValues *fv;
+    int num_formats = 0, j;
+    AVCodecContext *encctx = s->streams[0]->codec;
+
+    if (   s->nb_streams > 1
+        || encctx->codec_type != AVMEDIA_TYPE_VIDEO
+        || encctx->codec_id   != AV_CODEC_ID_RAWVIDEO) {
+        av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
+        return AVERROR(EINVAL);
+    }
+
+    xv->display = XOpenDisplay(xv->display_name);
+    if (!xv->display) {
+        av_log(s, AV_LOG_ERROR, "Could not open the X11 display '%s'\n", xv->display_name);
+        return AVERROR(EINVAL);
+    }
+
+    xv->image_width  = encctx->width;
+    xv->image_height = encctx->height;
+    if (!xv->window_width && !xv->window_height) {
+        xv->window_width  = encctx->width;
+        xv->window_height = encctx->height;
+    }
+    xv->window = XCreateSimpleWindow(xv->display, DefaultRootWindow(xv->display),
+                                     xv->window_x, xv->window_y,
+                                     xv->window_width, xv->window_height,
+                                     0, 0, 0);
+    if (!xv->window_title) {
+        if (!(xv->window_title = av_strdup(s->filename)))
+            return AVERROR(ENOMEM);
+    }
+    XStoreName(xv->display, xv->window, xv->window_title);
+    XMapWindow(xv->display, xv->window);
+
+    if (XvQueryAdaptors(xv->display, DefaultRootWindow(xv->display), &num_adaptors, &ai) != Success)
+        return AVERROR_EXTERNAL;
+    xv->xv_port = ai[0].base_id;
+
+    if (encctx->pix_fmt != AV_PIX_FMT_YUV420P) {
+        av_log(s, AV_LOG_ERROR,
+               "Unsupported pixel format '%s', only yuv420p is currently supported\n",
+               av_get_pix_fmt_name(encctx->pix_fmt));
+        return AVERROR_PATCHWELCOME;
+    }
+
+    fv = XvListImageFormats(xv->display, xv->xv_port, &num_formats);
+    if (!fv)
+        return AVERROR_EXTERNAL;
+    for (j = 0; j < num_formats; j++) {
+        if (fv[j].id == MKTAG('I','4','2','0')) {
+            break;
+        }
+    }
+    XFree(fv);
+
+    if (j >= num_formats) {
+        av_log(s, AV_LOG_ERROR,
+               "Device does not support pixel format yuv420p, aborting\n");
+        return AVERROR(EINVAL);
+    }
+
+    xv->gc = XCreateGC(xv->display, xv->window, 0, 0);
+    xv->image_width  = encctx->width;
+    xv->image_height = encctx->height;
+    xv->yuv_image = XvShmCreateImage(xv->display, xv->xv_port,
+                                     MKTAG('I','4','2','0'), 0,
+                                     xv->image_width, xv->image_height, &xv->yuv_shminfo);
+    xv->yuv_shminfo.shmid = shmget(IPC_PRIVATE, xv->yuv_image->data_size,
+                                   IPC_CREAT | 0777);
+    xv->yuv_shminfo.shmaddr = (char *)shmat(xv->yuv_shminfo.shmid, 0, 0);
+    xv->yuv_image->data = xv->yuv_shminfo.shmaddr;
+    xv->yuv_shminfo.readOnly = False;
+
+    XShmAttach(xv->display, &xv->yuv_shminfo);
+    XSync(xv->display, False);
+    shmctl(xv->yuv_shminfo.shmid, IPC_RMID, 0);
+
+    return 0;
+}
+
+static int xv_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    XVContext *xv = s->priv_data;
+    XvImage *img = xv->yuv_image;
+    XWindowAttributes window_attrs;
+    AVPicture pict;
+    AVCodecContext *ctx = s->streams[0]->codec;
+    int y, h;
+
+    h = img->height / 2;
+
+    avpicture_fill(&pict, pkt->data, ctx->pix_fmt, ctx->width, ctx->height);
+    for (y = 0; y < img->height; y++) {
+        memcpy(&img->data[img->offsets[0] + (y * img->pitches[0])],
+               &pict.data[0][y * pict.linesize[0]], img->pitches[0]);
+    }
+
+    for (y = 0; y < h; ++y) {
+        memcpy(&img->data[img->offsets[1] + (y * img->pitches[1])],
+               &pict.data[1][y * pict.linesize[1]], img->pitches[1]);
+        memcpy(&img->data[img->offsets[2] + (y * img->pitches[2])],
+               &pict.data[2][y * pict.linesize[2]], img->pitches[2]);
+    }
+
+    XGetWindowAttributes(xv->display, xv->window, &window_attrs);
+    if (XvShmPutImage(xv->display, xv->xv_port, xv->window, xv->gc,
+                      xv->yuv_image, 0, 0, xv->image_width, xv->image_height, 0, 0,
+                      window_attrs.width, window_attrs.height, True) != Success) {
+        av_log(s, AV_LOG_ERROR, "Could not copy image to XV shared memory buffer\n");
+        return AVERROR_EXTERNAL;
+    }
+    return 0;
+}
+
+static int xv_write_trailer(AVFormatContext *s)
+{
+    XVContext *xv = s->priv_data;
+
+    XShmDetach(xv->display, &xv->yuv_shminfo);
+    shmdt(xv->yuv_image->data);
+    XFree(xv->yuv_image);
+    XCloseDisplay(xv->display);
+    return 0;
+}
+
+#define OFFSET(x) offsetof(XVContext, x)
+static const AVOption options[] = {
+    { "display_name", "set display name",       OFFSET(display_name), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
+    { "window_size",  "set window forced size", OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
+    { "window_title", "set window title",       OFFSET(window_title), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
+    { "window_x",     "set window x offset",    OFFSET(window_x),     AV_OPT_TYPE_INT,    {.i64 = 0 }, -INT_MAX, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
+    { "window_y",     "set window y offset",    OFFSET(window_y),     AV_OPT_TYPE_INT,    {.i64 = 0 }, -INT_MAX, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
+    { NULL }
+
+};
+
+static const AVClass xv_class = {
+    .class_name = "xvideo outdev",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVOutputFormat ff_xv_muxer = {
+    .name           = "xv",
+    .long_name      = NULL_IF_CONFIG_SMALL("XV (XVideo) output device"),
+    .priv_data_size = sizeof(XVContext),
+    .audio_codec    = AV_CODEC_ID_NONE,
+    .video_codec    = AV_CODEC_ID_RAWVIDEO,
+    .write_header   = xv_write_header,
+    .write_packet   = xv_write_packet,
+    .write_trailer  = xv_write_trailer,
+    .flags          = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
+    .priv_class     = &xv_class,
+};