lavd: add fbdev output device

Signed-off-by: Lukasz Marek <lukasz.m.luki@gmail.com>
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>

1 files changed, 253 insertions, 0 deletions

diff --git a/libavdevice/fbdev_enc.c b/libavdevice/fbdev_enc.c
new file mode 100644
index 0000000..be93093
--- /dev/null
+++ b/libavdevice/fbdev_enc.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright (c) 2013 Lukasz Marek
+ *
+ * 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
+ */
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <linux/fb.h>
+#include "libavutil/pixdesc.h"
+#include "libavutil/log.h"
+#include "libavutil/mem.h"
+#include "libavutil/opt.h"
+#include "libavformat/avformat.h"
+
+typedef struct {
+    AVClass *class;                   ///< class for private options
+    int xoffset;                      ///< x coordinate of top left corner
+    int yoffset;                      ///< y coordinate of top left corner
+    struct fb_var_screeninfo varinfo; ///< framebuffer variable info
+    struct fb_fix_screeninfo fixinfo; ///< framebuffer fixed info
+    int fd;                           ///< framebuffer device file descriptor
+    int index;                        ///< index of a video stream
+    uint8_t *data;                    ///< framebuffer data
+} FBDevContext;
+
+struct rgb_pixfmt_map_entry {
+    int bits_per_pixel;
+    int red_offset, green_offset, blue_offset, alpha_offset;
+    enum AVPixelFormat pixfmt;
+};
+
+static const struct rgb_pixfmt_map_entry rgb_pixfmt_map[] = {
+    // bpp, red_offset,  green_offset, blue_offset, alpha_offset, pixfmt
+    {  32,       0,           8,          16,           24,   AV_PIX_FMT_RGBA  },
+    {  32,      16,           8,           0,           24,   AV_PIX_FMT_BGRA  },
+    {  32,       8,          16,          24,            0,   AV_PIX_FMT_ARGB  },
+    {  32,       3,           2,           8,            0,   AV_PIX_FMT_ABGR  },
+    {  24,       0,           8,          16,            0,   AV_PIX_FMT_RGB24 },
+    {  24,      16,           8,           0,            0,   AV_PIX_FMT_BGR24 },
+    {  16,      11,           5,           0,           16,   AV_PIX_FMT_RGB565 },
+};
+
+static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
+{
+    int i;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) {
+        const struct rgb_pixfmt_map_entry *entry = &rgb_pixfmt_map[i];
+        if (entry->bits_per_pixel == varinfo->bits_per_pixel &&
+            entry->red_offset     == varinfo->red.offset     &&
+            entry->green_offset   == varinfo->green.offset   &&
+            entry->blue_offset    == varinfo->blue.offset)
+            return entry->pixfmt;
+    }
+
+    return AV_PIX_FMT_NONE;
+}
+
+static av_cold int fbdev_write_header(AVFormatContext *h)
+{
+    FBDevContext *fbdev = h->priv_data;
+    enum AVPixelFormat pix_fmt;
+    AVStream *st = NULL;
+    int ret, flags = O_RDWR;
+
+    for (int i = 0; i < h->nb_streams; i++) {
+        if (h->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+            if (!st) {
+                fbdev->index = i;
+                st = h->streams[i];
+            } else {
+                av_log(h, AV_LOG_WARNING, "More than one video stream found. First one is used.\n");
+                break;
+            }
+        }
+    }
+    if (!st) {
+        av_log(h, AV_LOG_ERROR, "No video stream found.\n");
+        return AVERROR(EINVAL);
+    }
+
+    if ((fbdev->fd = avpriv_open(h->filename, flags)) == -1) {
+        ret = AVERROR(errno);
+        av_log(h, AV_LOG_ERROR,
+               "Could not open framebuffer device '%s': %s\n",
+               h->filename, av_err2str(ret));
+        return ret;
+    }
+
+    if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
+        ret = AVERROR(errno);
+        av_log(h, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
+        goto fail;
+    }
+
+    if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
+        ret = AVERROR(errno);
+        av_log(h, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
+        goto fail;
+    }
+
+    pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
+    if (pix_fmt == AV_PIX_FMT_NONE) {
+        ret = AVERROR(EINVAL);
+        av_log(h, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n");
+        goto fail;
+    }
+
+    fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_WRITE, MAP_SHARED, fbdev->fd, 0);
+    if (fbdev->data == MAP_FAILED) {
+        ret = AVERROR(errno);
+        av_log(h, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
+        goto fail;
+    }
+
+    return 0;
+  fail:
+    close(fbdev->fd);
+    return ret;
+}
+
+static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
+{
+    FBDevContext *fbdev = h->priv_data;
+    uint8_t *pin, *pout;
+    enum AVPixelFormat fb_pix_fmt;
+    int disp_height;
+    int bytes_to_copy;
+    AVCodecContext *codec_ctx = h->streams[fbdev->index]->codec;
+    enum AVPixelFormat video_pix_fmt = codec_ctx->pix_fmt;
+    int video_width = codec_ctx->width;
+    int video_height = codec_ctx->height;
+    int bytes_per_pixel = ((codec_ctx->bits_per_coded_sample + 7) >> 3);
+    int src_line_size = video_width * bytes_per_pixel;
+
+    if (fbdev->index != pkt->stream_index)
+        return 0;
+
+    if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
+        av_log(h, AV_LOG_WARNING,
+               "Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));
+
+    fb_pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
+
+    if (fb_pix_fmt != video_pix_fmt) {
+        av_log(h, AV_LOG_ERROR, "Pixel format %s is not supported, use %s\n",
+               av_get_pix_fmt_name(video_pix_fmt), av_get_pix_fmt_name(fb_pix_fmt));
+        return AVERROR(EINVAL);
+    }
+
+    disp_height = FFMIN(fbdev->varinfo.yres, video_height);
+    bytes_to_copy = FFMIN(fbdev->varinfo.xres, video_width) * bytes_per_pixel;
+
+    pin  = pkt->data;
+    pout = fbdev->data +
+           bytes_per_pixel * fbdev->varinfo.xoffset +
+           fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
+
+    if (fbdev->xoffset) {
+        if (fbdev->xoffset < 0) {
+            if (-fbdev->xoffset >= video_width) //nothing to display
+                return 0;
+            bytes_to_copy += fbdev->xoffset * bytes_per_pixel;
+            pin -= fbdev->xoffset * bytes_per_pixel;
+        } else {
+            int diff = (video_width + fbdev->xoffset) - fbdev->varinfo.xres;
+            if (diff > 0) {
+                if (diff >= video_width) //nothing to display
+                    return 0;
+                bytes_to_copy -= diff * bytes_per_pixel;
+            }
+            pout += bytes_per_pixel * fbdev->xoffset;
+        }
+    }
+
+    if (fbdev->yoffset) {
+        if (fbdev->yoffset < 0) {
+            if (-fbdev->yoffset >= video_height) //nothing to display
+                return 0;
+            disp_height += fbdev->yoffset;
+            pin -= fbdev->yoffset * src_line_size;
+        } else {
+            int diff = (video_height + fbdev->yoffset) - fbdev->varinfo.yres;
+            if (diff > 0) {
+                if (diff >= video_height) //nothing to display
+                    return 0;
+                disp_height -= diff;
+            }
+            pout += fbdev->yoffset * fbdev->fixinfo.line_length;
+        }
+    }
+
+    for (int i = 0; i < disp_height; i++) {
+        memcpy(pout, pin, bytes_to_copy);
+        pout += fbdev->fixinfo.line_length;
+        pin  += src_line_size;
+    }
+
+    return 0;
+}
+
+static av_cold int fbdev_write_trailer(AVFormatContext *h)
+{
+    FBDevContext *fbdev = h->priv_data;
+    munmap(fbdev->data, fbdev->fixinfo.smem_len);
+    close(fbdev->fd);
+    return 0;
+}
+
+#define OFFSET(x) offsetof(FBDevContext, x)
+#define ENC AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "xoffset", "set x coordinate of top left corner", OFFSET(xoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
+    { "yoffset", "set y coordinate of top left corner", OFFSET(yoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
+    { NULL }
+};
+
+static const AVClass fbdev_class = {
+    .class_name = "fbdev outdev",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVOutputFormat ff_fbdev_muxer = {
+    .name           = "fbdev",
+    .long_name      = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
+    .priv_data_size = sizeof(FBDevContext),
+    .audio_codec    = AV_CODEC_ID_NONE,
+    .video_codec    = AV_CODEC_ID_RAWVIDEO,
+    .write_header   = fbdev_write_header,
+    .write_packet   = fbdev_write_packet,
+    .write_trailer  = fbdev_write_trailer,
+    .flags          = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
+    .priv_class     = &fbdev_class,
+};