diff mbox series

[2/3] add vnc h264 encoder

Message ID 20250407105939.1997660-2-dietmar@proxmox.com (mailing list archive)
State New
Headers show
Series [1/3] new configure option to enable gstreamer | expand

Commit Message

Dietmar Maurer April 7, 2025, 10:59 a.m. UTC
Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
---
 ui/meson.build    |   1 +
 ui/vnc-enc-h264.c | 269 ++++++++++++++++++++++++++++++++++++++++++++++
 ui/vnc-jobs.c     |  49 ++++++---
 ui/vnc.c          |  21 ++++
 ui/vnc.h          |  21 ++++
 5 files changed, 346 insertions(+), 15 deletions(-)
 create mode 100644 ui/vnc-enc-h264.c

Comments

Marc-André Lureau April 7, 2025, 8:36 p.m. UTC | #1
Hi

Please resend the series with a cover letter
(https://www.qemu.org/docs/master/devel/submitting-a-patch.html#use-git-format-patch)

Some people prefer when the commit message has content too :)

At least, it would be useful if you point to a client that supports
the codec and allow us to test/use it.

Also documentation: this should be
https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#open-h-264-encoding
I suppose

On Mon, Apr 7, 2025 at 3:06 PM Dietmar Maurer <dietmar@proxmox.com> wrote:
>
> Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
> ---
>  ui/meson.build    |   1 +
>  ui/vnc-enc-h264.c | 269 ++++++++++++++++++++++++++++++++++++++++++++++
>  ui/vnc-jobs.c     |  49 ++++++---
>  ui/vnc.c          |  21 ++++
>  ui/vnc.h          |  21 ++++
>  5 files changed, 346 insertions(+), 15 deletions(-)
>  create mode 100644 ui/vnc-enc-h264.c
>
> diff --git a/ui/meson.build b/ui/meson.build
> index 35fb04cadf..34f1f33699 100644
> --- a/ui/meson.build
> +++ b/ui/meson.build
> @@ -46,6 +46,7 @@ vnc_ss.add(files(
>  ))
>  vnc_ss.add(zlib, jpeg)
>  vnc_ss.add(when: sasl, if_true: files('vnc-auth-sasl.c'))
> +vnc_ss.add(when: gstreamer, if_true: files('vnc-enc-h264.c'))
>  system_ss.add_all(when: [vnc, pixman], if_true: vnc_ss)
>  system_ss.add(when: vnc, if_false: files('vnc-stubs.c'))
>
> diff --git a/ui/vnc-enc-h264.c b/ui/vnc-enc-h264.c
> new file mode 100644
> index 0000000000..ca8e206335
> --- /dev/null
> +++ b/ui/vnc-enc-h264.c
> @@ -0,0 +1,269 @@
> +#include "qemu/osdep.h"
> +#include "vnc.h"
> +
> +#include <gst/gst.h>
> +
> +static void libavcodec_destroy_encoder_context(VncState *vs)

it's not libavcodec.

> +{
> +    if (!vs->h264) {
> +        return;
> +    }
> +
> +    if (vs->h264->source) {
> +        gst_object_unref(vs->h264->source);
> +        vs->h264->source = NULL;
> +    }
> +
> +    if (vs->h264->convert) {
> +        gst_object_unref(vs->h264->convert);
> +        vs->h264->convert = NULL;
> +    }
> +
> +    if (vs->h264->gst_encoder) {
> +        gst_object_unref(vs->h264->gst_encoder);
> +        vs->h264->sink = NULL;
> +    }
> +
> +    if (vs->h264->sink) {
> +        gst_object_unref(vs->h264->sink);
> +        vs->h264->sink = NULL;
> +    }
> +
> +    if (vs->h264->pipeline) {
> +        gst_object_unref(vs->h264->pipeline);
> +        vs->h264->pipeline = NULL;
> +    }
> +}
> +
> +static bool libavcodec_create_encoder_context(VncState *vs, int w, int h)
> +{
> +    g_assert(vs->h264 != NULL);
> +
> +    if (vs->h264->sink) {
> +        if (w != vs->h264->width || h != vs->h264->height) {
> +            libavcodec_destroy_encoder_context(vs);
> +        }
> +    }
> +
> +    if (vs->h264->sink) {
> +        return TRUE;
> +    }
> +
> +    vs->h264->width = w;
> +    vs->h264->height = h;
> +
> +    vs->h264->source = gst_element_factory_make("appsrc", "source");
> +    if (!vs->h264->source) {
> +        VNC_DEBUG("Could not create gst source\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    vs->h264->convert = gst_element_factory_make("videoconvert", "convert");
> +    if (!vs->h264->convert) {
> +        VNC_DEBUG("Could not create gst convert element\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    vs->h264->gst_encoder = gst_element_factory_make("x264enc", "gst-encoder");

It's libx264. And that might be an issue, since it's not generally
available (not in Fedora).

Have you tried to make it agnostic to the encoder element thanks to
encodebin instead?

> +    if (!vs->h264->gst_encoder) {
> +        VNC_DEBUG("Could not create gst x264 encoder\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    g_object_set(vs->h264->gst_encoder, "tune", 4, NULL); /* zerolatency */
> +    /* fix for zerolatency with novnc (without, noVNC displays green stripes) */
> +    g_object_set(vs->h264->gst_encoder, "threads", 1, NULL);
> +
> +    g_object_set(vs->h264->gst_encoder, "pass", 5, NULL); /* Constant Quality */
> +    g_object_set(vs->h264->gst_encoder, "quantizer", 26, NULL);
> +
> +    /* avoid access unit delimiters (Nal Unit Type 9) - not required */
> +    g_object_set(vs->h264->gst_encoder, "aud", false, NULL);
> +
> +    vs->h264->sink = gst_element_factory_make("appsink", "sink");
> +    if (!vs->h264->sink) {
> +        VNC_DEBUG("Could not create gst sink\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    vs->h264->pipeline = gst_pipeline_new("vnc-h264-pipeline");
> +    if (!vs->h264->pipeline) {
> +        VNC_DEBUG("Could not create gst pipeline\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    gst_object_ref(vs->h264->source);
> +    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->source)) {
> +        gst_object_unref(vs->h264->source);
> +        VNC_DEBUG("Could not add source to gst pipeline\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    gst_object_ref(vs->h264->convert);
> +    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->convert)) {
> +        gst_object_unref(vs->h264->convert);
> +        VNC_DEBUG("Could not add convert to gst pipeline\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    gst_object_ref(vs->h264->gst_encoder);
> +    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->gst_encoder)) {
> +        gst_object_unref(vs->h264->gst_encoder);
> +        VNC_DEBUG("Could not add encoder to gst pipeline\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    gst_object_ref(vs->h264->sink);
> +    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->sink)) {
> +        gst_object_unref(vs->h264->sink);
> +        VNC_DEBUG("Could not add sink to gst pipeline\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    GstCaps *source_caps = gst_caps_new_simple(
> +        "video/x-raw",
> +        "format", G_TYPE_STRING, "BGRx",
> +        "framerate", GST_TYPE_FRACTION, 33, 1,
> +        "width", G_TYPE_INT, w,
> +        "height", G_TYPE_INT, h,
> +        NULL);
> +
> +    if (!source_caps) {
> +        VNC_DEBUG("Could not create source caps filter\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    g_object_set(vs->h264->source, "caps", source_caps, NULL);
> +    gst_caps_unref(source_caps);
> +
> +    if (gst_element_link_many(
> +            vs->h264->source,
> +            vs->h264->convert,
> +            vs->h264->gst_encoder,
> +            vs->h264->sink,
> +            NULL
> +        ) != TRUE) {
> +        VNC_DEBUG("Elements could not be linked.\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    /* Start playing */
> +    int ret = gst_element_set_state(vs->h264->pipeline, GST_STATE_PLAYING);
> +    if (ret == GST_STATE_CHANGE_FAILURE) {
> +        VNC_DEBUG("Unable to set the pipeline to the playing state.\n");
> +        libavcodec_destroy_encoder_context(vs);
> +        return FALSE;
> +    }
> +
> +    return TRUE;
> +}
> +
> +int vnc_h264_encoder_init(VncState *vs)
> +{
> +    g_assert(vs->h264 == NULL);
> +
> +    vs->h264 = g_malloc0(sizeof(VncH264));
> +
> +    return 0;
> +}
> +
> +int vnc_h264_send_framebuffer_update(
> +    VncState *vs,
> +    int _x,
> +    int _y,
> +    int _w,
> +    int _h,
> +) {
> +    g_assert(vs->h264 != NULL);
> +    g_assert(vs->vd != NULL);
> +    g_assert(vs->vd->server != NULL);
> +
> +    int width = pixman_image_get_width(vs->vd->server);
> +    int height = pixman_image_get_height(vs->vd->server);
> +
> +    g_assert(width == vs->client_width);
> +    g_assert(height == vs->client_height);
> +
> +    int rdb_h264_flags = 0;
> +
> +    if (vs->h264->sink) {
> +        if (width != vs->h264->width || height != vs->h264->height) {
> +            rdb_h264_flags = 2;
> +        }
> +    } else {
> +        rdb_h264_flags = 2;
> +    }
> +
> +    if (!libavcodec_create_encoder_context(vs, width, height)) {
> +        VNC_DEBUG("Create encoder context failed\n");
> +        return -1;
> +    }
> +
> +    g_assert(vs->h264->sink != NULL);
> +
> +    uint8_t *src_data_ptr = vnc_server_fb_ptr(vs->vd, 0, 0);
> +    size_t src_data_size = width * height * VNC_SERVER_FB_BYTES;
> +
> +    GstBuffer *buffer = gst_buffer_new_wrapped_full(
> +        0, src_data_ptr, src_data_size, 0, src_data_size, NULL, NULL);
> +
> +    GstFlowReturn ret;
> +    g_signal_emit_by_name(vs->h264->source, "push-buffer", buffer, &ret);
> +
> +    if (ret != GST_FLOW_OK) {
> +        VNC_DEBUG("gst appsrc push buffer failed\n");
> +        return -1;
> +    }
> +
> +    GstSample *sample;
> +    /* Retrieve the buffer */
> +    g_signal_emit_by_name(vs->h264->sink, "pull-sample", &sample);
> +    if (sample) {
> +        GstBuffer *buf = gst_sample_get_buffer(sample);
> +        GstMapInfo map;
> +        if (gst_buffer_map(buf, &map, 0)) {
> +            vnc_framebuffer_update(vs, 0, 0, width, height, VNC_ENCODING_H264);
> +            vnc_write_s32(vs, map.size); /* write data length */
> +            vnc_write_s32(vs, rdb_h264_flags); /* write flags */
> +            rdb_h264_flags = 0;
> +
> +            VNC_DEBUG("GST vnc_h264_update send %ld\n", map.size);
> +
> +            vnc_write(vs, map.data, map.size);
> +
> +            gst_buffer_unmap(buf, &map);
> +
> +            return 1;
> +        } else {
> +            VNC_DEBUG("unable to map sample\n");
> +        }
> +        gst_sample_unref(sample);
> +        return 1;
> +    } else {
> +        VNC_DEBUG("gst no data\n");
> +        return 0;
> +    }
> +}
> +
> +void vnc_h264_clear(VncState *vs)
> +{
> +    if (!vs->h264) {
> +        return;
> +    }
> +
> +    libavcodec_destroy_encoder_context(vs);
> +
> +    g_free(vs->h264);
> +    vs->h264 = NULL;
> +}
> diff --git a/ui/vnc-jobs.c b/ui/vnc-jobs.c
> index fcca7ec632..853a547d9a 100644
> --- a/ui/vnc-jobs.c
> +++ b/ui/vnc-jobs.c
> @@ -193,6 +193,7 @@ static void vnc_async_encoding_start(VncState *orig, VncState *local)
>      local->zlib = orig->zlib;
>      local->hextile = orig->hextile;
>      local->zrle = orig->zrle;
> +    local->h264 = orig->h264;
>      local->client_width = orig->client_width;
>      local->client_height = orig->client_height;
>  }
> @@ -204,6 +205,7 @@ static void vnc_async_encoding_end(VncState *orig, VncState *local)
>      orig->zlib = local->zlib;
>      orig->hextile = local->hextile;
>      orig->zrle = local->zrle;
> +    orig->h264 = local->h264;
>      orig->lossy_rect = local->lossy_rect;
>  }
>
> @@ -284,25 +286,42 @@ static int vnc_worker_thread_loop(VncJobQueue *queue)
>      vnc_write_u16(&vs, 0);
>
>      vnc_lock_display(job->vs->vd);
> -    QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
> -        int n;
> -
> -        if (job->vs->ioc == NULL) {
> -            vnc_unlock_display(job->vs->vd);
> -            /* Copy persistent encoding data */
> -            vnc_async_encoding_end(job->vs, &vs);
> -            goto disconnected;
> -        }
>
> -        if (vnc_worker_clamp_rect(&vs, job, &entry->rect)) {
> -            n = vnc_send_framebuffer_update(&vs, entry->rect.x, entry->rect.y,
> -                                            entry->rect.w, entry->rect.h);
> +    if (vs.vnc_encoding == VNC_ENCODING_H264) {
> +        int width = pixman_image_get_width(vs.vd->server);
> +        int height = pixman_image_get_height(vs.vd->server);
> +           int n = vnc_send_framebuffer_update(&vs, 0, 0, width, height);
> +        if (n >= 0) {
> +            n_rectangles += n;
> +        }
> +        QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
> +            g_free(entry);
> +        }
> +    } else {
> +        QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
> +            int n;
> +
> +            if (job->vs->ioc == NULL) {
> +                vnc_unlock_display(job->vs->vd);
> +                /* Copy persistent encoding data */
> +                vnc_async_encoding_end(job->vs, &vs);
> +                goto disconnected;
> +            }
>
> -            if (n >= 0) {
> -                n_rectangles += n;
> +            if (vnc_worker_clamp_rect(&vs, job, &entry->rect)) {
> +                n = vnc_send_framebuffer_update(
> +                    &vs,
> +                    entry->rect.x,
> +                    entry->rect.y,
> +                    entry->rect.w,
> +                    entry->rect.h);
> +
> +                if (n >= 0) {
> +                    n_rectangles += n;
> +                }
>              }
> +            g_free(entry);
>          }
> -        g_free(entry);
>      }
>      trace_vnc_job_nrects(&vs, job, n_rectangles);
>      vnc_unlock_display(job->vs->vd);
> diff --git a/ui/vnc.c b/ui/vnc.c
> index 9241caaad9..2e60b55e47 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -972,6 +972,9 @@ int vnc_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
>          case VNC_ENCODING_ZYWRLE:
>              n = vnc_zywrle_send_framebuffer_update(vs, x, y, w, h);
>              break;
> +        case VNC_ENCODING_H264:
> +            n = vnc_h264_send_framebuffer_update(vs, x, y, w, h);
> +            break;
>          default:
>              vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_RAW);
>              n = vnc_raw_send_framebuffer_update(vs, x, y, w, h);
> @@ -1326,6 +1329,10 @@ void vnc_disconnect_finish(VncState *vs)
>      vnc_tight_clear(vs);
>      vnc_zrle_clear(vs);
>
> +#ifdef CONFIG_GSTREAMER
> +    vnc_h264_clear(vs);
> +#endif
> +
>  #ifdef CONFIG_VNC_SASL
>      vnc_sasl_client_cleanup(vs);
>  #endif /* CONFIG_VNC_SASL */
> @@ -2181,6 +2188,16 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
>              vnc_set_feature(vs, VNC_FEATURE_ZYWRLE);
>              vs->vnc_encoding = enc;
>              break;
> +#ifdef CONFIG_GSTREAMER
> +        case VNC_ENCODING_H264:
> +            if (vnc_h264_encoder_init(vs) == 0) {
> +                vnc_set_feature(vs, VNC_FEATURE_H264);

Before advertising support for the codec, it should actually check if
the encoder is present. It would also be useful to have an extra VNC
option like H264=on/off/auto.

> +                vs->vnc_encoding = enc;
> +            } else {
> +                VNC_DEBUG("vnc_h264_encoder_init failed\n");
> +            }
> +            break;
> +#endif
>          case VNC_ENCODING_DESKTOPRESIZE:
>              vnc_set_feature(vs, VNC_FEATURE_RESIZE);
>              break;
> @@ -4291,6 +4308,10 @@ int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp)
>      Error *local_err = NULL;
>      char *id = (char *)qemu_opts_id(opts);
>
> +#ifdef CONFIG_GSTREAMER
> +    gst_init(NULL, NULL);
> +#endif
> +
>      assert(id);
>      vnc_display_init(id, &local_err);
>      if (local_err) {
> diff --git a/ui/vnc.h b/ui/vnc.h
> index acc53a2cc1..7e232f7dac 100644
> --- a/ui/vnc.h
> +++ b/ui/vnc.h
> @@ -46,6 +46,10 @@
>  #include "vnc-enc-zrle.h"
>  #include "ui/kbd-state.h"
>
> +#ifdef CONFIG_GSTREAMER
> +#include <gst/gst.h>
> +#endif
> +
>  // #define _VNC_DEBUG 1
>
>  #ifdef _VNC_DEBUG
> @@ -231,6 +235,14 @@ typedef struct VncZywrle {
>      int buf[VNC_ZRLE_TILE_WIDTH * VNC_ZRLE_TILE_HEIGHT];
>  } VncZywrle;
>
> +#ifdef CONFIG_GSTREAMER
> +typedef struct VncH264 {
> +    GstElement *pipeline, *source, *gst_encoder, *sink, *convert;
> +    size_t width;
> +    size_t height;
> +} VncH264;
> +#endif
> +
>  struct VncRect
>  {
>      int x;
> @@ -344,6 +356,9 @@ struct VncState
>      VncHextile hextile;
>      VncZrle *zrle;
>      VncZywrle zywrle;
> +#ifdef CONFIG_GSTREAMER
> +    VncH264 *h264;
> +#endif
>
>      Notifier mouse_mode_notifier;
>
> @@ -404,6 +419,7 @@ enum {
>  #define VNC_ENCODING_TRLE                 0x0000000f
>  #define VNC_ENCODING_ZRLE                 0x00000010
>  #define VNC_ENCODING_ZYWRLE               0x00000011
> +#define VNC_ENCODING_H264                 0x00000032 /* 50   */
>  #define VNC_ENCODING_COMPRESSLEVEL0       0xFFFFFF00 /* -256 */
>  #define VNC_ENCODING_QUALITYLEVEL0        0xFFFFFFE0 /* -32  */
>  #define VNC_ENCODING_XCURSOR              0xFFFFFF10 /* -240 */
> @@ -464,6 +480,7 @@ enum VncFeatures {
>      VNC_FEATURE_XVP,
>      VNC_FEATURE_CLIPBOARD_EXT,
>      VNC_FEATURE_AUDIO,
> +    VNC_FEATURE_H264,
>  };
>
>
> @@ -625,6 +642,10 @@ int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
>  int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
>  void vnc_zrle_clear(VncState *vs);
>
> +int vnc_h264_encoder_init(VncState *vs);
> +int vnc_h264_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
> +void vnc_h264_clear(VncState *vs);
> +
>  /* vnc-clipboard.c */
>  void vnc_server_cut_text_caps(VncState *vs);
>  void vnc_client_cut_text(VncState *vs, size_t len, uint8_t *text);
> --
> 2.39.5
>
Dietmar Maurer April 8, 2025, 9:53 a.m. UTC | #2
> Please resend the series with a cover letter
> (https://www.qemu.org/docs/master/devel/submitting-a-patch.html#use-git-format-patch)

Ok, just resend this series with a cover letter and commit message.
(patches unchanged)

> > +#include <gst/gst.h>
> > +
> > +static void libavcodec_destroy_encoder_context(VncState *vs)
> 
> it's not libavcodec.

I will fix that in v2.


> > +#ifdef CONFIG_GSTREAMER
> > +        case VNC_ENCODING_H264:
> > +            if (vnc_h264_encoder_init(vs) == 0) {
> > +                vnc_set_feature(vs, VNC_FEATURE_H264);
> 
> Before advertising support for the codec, it should actually check if
> the encoder is present.

ok.

> It would also be useful to have an extra VNC
> option like H264=on/off/auto.

I thought it would be better to do that at the client?
Marc-André Lureau April 8, 2025, 10:37 a.m. UTC | #3
Hi

On Tue, Apr 8, 2025 at 1:54 PM Dietmar Maurer <dietmar@proxmox.com> wrote:
>
> > Please resend the series with a cover letter
> > (https://www.qemu.org/docs/master/devel/submitting-a-patch.html#use-git-format-patch)
>
> Ok, just resend this series with a cover letter and commit message.
> (patches unchanged)

ok, thanks

>
> > > +#include <gst/gst.h>
> > > +
> > > +static void libavcodec_destroy_encoder_context(VncState *vs)
> >
> > it's not libavcodec.
>
> I will fix that in v2.

What about encodebin suggestion?

>
>
> > > +#ifdef CONFIG_GSTREAMER
> > > +        case VNC_ENCODING_H264:
> > > +            if (vnc_h264_encoder_init(vs) == 0) {
> > > +                vnc_set_feature(vs, VNC_FEATURE_H264);
> >
> > Before advertising support for the codec, it should actually check if
> > the encoder is present.
>
> ok.
>
> > It would also be useful to have an extra VNC
> > option like H264=on/off/auto.
>
> I thought it would be better to do that at the client?

Well, it can be worth it to prevent h264 usage from the server too. Or
to ensure the server is h264-capable. (this wasn't seen as much
necessary for other codecs that are low-resource and/or patent-free,
but may make sense too)
Dietmar Maurer April 8, 2025, 11:10 a.m. UTC | #4
> > > > +#include <gst/gst.h>
> > > > +
> > > > +static void libavcodec_destroy_encoder_context(VncState *vs)
> > >
> > > it's not libavcodec.
> >
> > I will fix that in v2.
> 
> What about encodebin suggestion?

I found no way to configure codec specific option (i.e. x264 zerolatency). I there a way? It is crucial to set those option
to get reasonable quality.

Anyway, I can test a view option, for example x264, openh264, and
maybe vah264enc (hardware support), and then simply use what is available.

I think we should also have the option to allow h264 if we detect
HW support, but disable software encoders. Or let the user select
the list of allowed codec?

> >
> > > > +#ifdef CONFIG_GSTREAMER
> > > > +        case VNC_ENCODING_H264:
> > > > +            if (vnc_h264_encoder_init(vs) == 0) {
> > > > +                vnc_set_feature(vs, VNC_FEATURE_H264);
> > >
> > > Before advertising support for the codec, it should actually check if
> > > the encoder is present.
> >
> > ok.
> >
> > > It would also be useful to have an extra VNC
> > > option like H264=on/off/auto.
> >
> > I thought it would be better to do that at the client?
> 
> Well, it can be worth it to prevent h264 usage from the server too. Or
> to ensure the server is h264-capable. (this wasn't seen as much
> necessary for other codecs that are low-resource and/or patent-free,
> but may make sense too)

Maybe H264=on,off,codec-list

on: automatically select the codec
off: disable h264
codec-list: a list of allowed codecs


- Dietmar
diff mbox series

Patch

diff --git a/ui/meson.build b/ui/meson.build
index 35fb04cadf..34f1f33699 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -46,6 +46,7 @@  vnc_ss.add(files(
 ))
 vnc_ss.add(zlib, jpeg)
 vnc_ss.add(when: sasl, if_true: files('vnc-auth-sasl.c'))
+vnc_ss.add(when: gstreamer, if_true: files('vnc-enc-h264.c'))
 system_ss.add_all(when: [vnc, pixman], if_true: vnc_ss)
 system_ss.add(when: vnc, if_false: files('vnc-stubs.c'))
 
diff --git a/ui/vnc-enc-h264.c b/ui/vnc-enc-h264.c
new file mode 100644
index 0000000000..ca8e206335
--- /dev/null
+++ b/ui/vnc-enc-h264.c
@@ -0,0 +1,269 @@ 
+#include "qemu/osdep.h"
+#include "vnc.h"
+
+#include <gst/gst.h>
+
+static void libavcodec_destroy_encoder_context(VncState *vs)
+{
+    if (!vs->h264) {
+        return;
+    }
+
+    if (vs->h264->source) {
+        gst_object_unref(vs->h264->source);
+        vs->h264->source = NULL;
+    }
+
+    if (vs->h264->convert) {
+        gst_object_unref(vs->h264->convert);
+        vs->h264->convert = NULL;
+    }
+
+    if (vs->h264->gst_encoder) {
+        gst_object_unref(vs->h264->gst_encoder);
+        vs->h264->sink = NULL;
+    }
+
+    if (vs->h264->sink) {
+        gst_object_unref(vs->h264->sink);
+        vs->h264->sink = NULL;
+    }
+
+    if (vs->h264->pipeline) {
+        gst_object_unref(vs->h264->pipeline);
+        vs->h264->pipeline = NULL;
+    }
+}
+
+static bool libavcodec_create_encoder_context(VncState *vs, int w, int h)
+{
+    g_assert(vs->h264 != NULL);
+
+    if (vs->h264->sink) {
+        if (w != vs->h264->width || h != vs->h264->height) {
+            libavcodec_destroy_encoder_context(vs);
+        }
+    }
+
+    if (vs->h264->sink) {
+        return TRUE;
+    }
+
+    vs->h264->width = w;
+    vs->h264->height = h;
+
+    vs->h264->source = gst_element_factory_make("appsrc", "source");
+    if (!vs->h264->source) {
+        VNC_DEBUG("Could not create gst source\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    vs->h264->convert = gst_element_factory_make("videoconvert", "convert");
+    if (!vs->h264->convert) {
+        VNC_DEBUG("Could not create gst convert element\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    vs->h264->gst_encoder = gst_element_factory_make("x264enc", "gst-encoder");
+    if (!vs->h264->gst_encoder) {
+        VNC_DEBUG("Could not create gst x264 encoder\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    g_object_set(vs->h264->gst_encoder, "tune", 4, NULL); /* zerolatency */
+    /* fix for zerolatency with novnc (without, noVNC displays green stripes) */
+    g_object_set(vs->h264->gst_encoder, "threads", 1, NULL);
+
+    g_object_set(vs->h264->gst_encoder, "pass", 5, NULL); /* Constant Quality */
+    g_object_set(vs->h264->gst_encoder, "quantizer", 26, NULL);
+
+    /* avoid access unit delimiters (Nal Unit Type 9) - not required */
+    g_object_set(vs->h264->gst_encoder, "aud", false, NULL);
+
+    vs->h264->sink = gst_element_factory_make("appsink", "sink");
+    if (!vs->h264->sink) {
+        VNC_DEBUG("Could not create gst sink\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    vs->h264->pipeline = gst_pipeline_new("vnc-h264-pipeline");
+    if (!vs->h264->pipeline) {
+        VNC_DEBUG("Could not create gst pipeline\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    gst_object_ref(vs->h264->source);
+    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->source)) {
+        gst_object_unref(vs->h264->source);
+        VNC_DEBUG("Could not add source to gst pipeline\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    gst_object_ref(vs->h264->convert);
+    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->convert)) {
+        gst_object_unref(vs->h264->convert);
+        VNC_DEBUG("Could not add convert to gst pipeline\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    gst_object_ref(vs->h264->gst_encoder);
+    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->gst_encoder)) {
+        gst_object_unref(vs->h264->gst_encoder);
+        VNC_DEBUG("Could not add encoder to gst pipeline\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    gst_object_ref(vs->h264->sink);
+    if (!gst_bin_add(GST_BIN(vs->h264->pipeline), vs->h264->sink)) {
+        gst_object_unref(vs->h264->sink);
+        VNC_DEBUG("Could not add sink to gst pipeline\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    GstCaps *source_caps = gst_caps_new_simple(
+        "video/x-raw",
+        "format", G_TYPE_STRING, "BGRx",
+        "framerate", GST_TYPE_FRACTION, 33, 1,
+        "width", G_TYPE_INT, w,
+        "height", G_TYPE_INT, h,
+        NULL);
+
+    if (!source_caps) {
+        VNC_DEBUG("Could not create source caps filter\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    g_object_set(vs->h264->source, "caps", source_caps, NULL);
+    gst_caps_unref(source_caps);
+
+    if (gst_element_link_many(
+            vs->h264->source,
+            vs->h264->convert,
+            vs->h264->gst_encoder,
+            vs->h264->sink,
+            NULL
+        ) != TRUE) {
+        VNC_DEBUG("Elements could not be linked.\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    /* Start playing */
+    int ret = gst_element_set_state(vs->h264->pipeline, GST_STATE_PLAYING);
+    if (ret == GST_STATE_CHANGE_FAILURE) {
+        VNC_DEBUG("Unable to set the pipeline to the playing state.\n");
+        libavcodec_destroy_encoder_context(vs);
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+int vnc_h264_encoder_init(VncState *vs)
+{
+    g_assert(vs->h264 == NULL);
+
+    vs->h264 = g_malloc0(sizeof(VncH264));
+
+    return 0;
+}
+
+int vnc_h264_send_framebuffer_update(
+    VncState *vs,
+    int _x,
+    int _y,
+    int _w,
+    int _h,
+) {
+    g_assert(vs->h264 != NULL);
+    g_assert(vs->vd != NULL);
+    g_assert(vs->vd->server != NULL);
+
+    int width = pixman_image_get_width(vs->vd->server);
+    int height = pixman_image_get_height(vs->vd->server);
+
+    g_assert(width == vs->client_width);
+    g_assert(height == vs->client_height);
+
+    int rdb_h264_flags = 0;
+
+    if (vs->h264->sink) {
+        if (width != vs->h264->width || height != vs->h264->height) {
+            rdb_h264_flags = 2;
+        }
+    } else {
+        rdb_h264_flags = 2;
+    }
+
+    if (!libavcodec_create_encoder_context(vs, width, height)) {
+        VNC_DEBUG("Create encoder context failed\n");
+        return -1;
+    }
+
+    g_assert(vs->h264->sink != NULL);
+
+    uint8_t *src_data_ptr = vnc_server_fb_ptr(vs->vd, 0, 0);
+    size_t src_data_size = width * height * VNC_SERVER_FB_BYTES;
+
+    GstBuffer *buffer = gst_buffer_new_wrapped_full(
+        0, src_data_ptr, src_data_size, 0, src_data_size, NULL, NULL);
+
+    GstFlowReturn ret;
+    g_signal_emit_by_name(vs->h264->source, "push-buffer", buffer, &ret);
+
+    if (ret != GST_FLOW_OK) {
+        VNC_DEBUG("gst appsrc push buffer failed\n");
+        return -1;
+    }
+
+    GstSample *sample;
+    /* Retrieve the buffer */
+    g_signal_emit_by_name(vs->h264->sink, "pull-sample", &sample);
+    if (sample) {
+        GstBuffer *buf = gst_sample_get_buffer(sample);
+        GstMapInfo map;
+        if (gst_buffer_map(buf, &map, 0)) {
+            vnc_framebuffer_update(vs, 0, 0, width, height, VNC_ENCODING_H264);
+            vnc_write_s32(vs, map.size); /* write data length */
+            vnc_write_s32(vs, rdb_h264_flags); /* write flags */
+            rdb_h264_flags = 0;
+
+            VNC_DEBUG("GST vnc_h264_update send %ld\n", map.size);
+
+            vnc_write(vs, map.data, map.size);
+
+            gst_buffer_unmap(buf, &map);
+
+            return 1;
+        } else {
+            VNC_DEBUG("unable to map sample\n");
+        }
+        gst_sample_unref(sample);
+        return 1;
+    } else {
+        VNC_DEBUG("gst no data\n");
+        return 0;
+    }
+}
+
+void vnc_h264_clear(VncState *vs)
+{
+    if (!vs->h264) {
+        return;
+    }
+
+    libavcodec_destroy_encoder_context(vs);
+
+    g_free(vs->h264);
+    vs->h264 = NULL;
+}
diff --git a/ui/vnc-jobs.c b/ui/vnc-jobs.c
index fcca7ec632..853a547d9a 100644
--- a/ui/vnc-jobs.c
+++ b/ui/vnc-jobs.c
@@ -193,6 +193,7 @@  static void vnc_async_encoding_start(VncState *orig, VncState *local)
     local->zlib = orig->zlib;
     local->hextile = orig->hextile;
     local->zrle = orig->zrle;
+    local->h264 = orig->h264;
     local->client_width = orig->client_width;
     local->client_height = orig->client_height;
 }
@@ -204,6 +205,7 @@  static void vnc_async_encoding_end(VncState *orig, VncState *local)
     orig->zlib = local->zlib;
     orig->hextile = local->hextile;
     orig->zrle = local->zrle;
+    orig->h264 = local->h264;
     orig->lossy_rect = local->lossy_rect;
 }
 
@@ -284,25 +286,42 @@  static int vnc_worker_thread_loop(VncJobQueue *queue)
     vnc_write_u16(&vs, 0);
 
     vnc_lock_display(job->vs->vd);
-    QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
-        int n;
-
-        if (job->vs->ioc == NULL) {
-            vnc_unlock_display(job->vs->vd);
-            /* Copy persistent encoding data */
-            vnc_async_encoding_end(job->vs, &vs);
-            goto disconnected;
-        }
 
-        if (vnc_worker_clamp_rect(&vs, job, &entry->rect)) {
-            n = vnc_send_framebuffer_update(&vs, entry->rect.x, entry->rect.y,
-                                            entry->rect.w, entry->rect.h);
+    if (vs.vnc_encoding == VNC_ENCODING_H264) {
+        int width = pixman_image_get_width(vs.vd->server);
+        int height = pixman_image_get_height(vs.vd->server);
+           int n = vnc_send_framebuffer_update(&vs, 0, 0, width, height);
+        if (n >= 0) {
+            n_rectangles += n;
+        }
+        QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
+            g_free(entry);
+        }
+    } else {
+        QLIST_FOREACH_SAFE(entry, &job->rectangles, next, tmp) {
+            int n;
+
+            if (job->vs->ioc == NULL) {
+                vnc_unlock_display(job->vs->vd);
+                /* Copy persistent encoding data */
+                vnc_async_encoding_end(job->vs, &vs);
+                goto disconnected;
+            }
 
-            if (n >= 0) {
-                n_rectangles += n;
+            if (vnc_worker_clamp_rect(&vs, job, &entry->rect)) {
+                n = vnc_send_framebuffer_update(
+                    &vs,
+                    entry->rect.x,
+                    entry->rect.y,
+                    entry->rect.w,
+                    entry->rect.h);
+
+                if (n >= 0) {
+                    n_rectangles += n;
+                }
             }
+            g_free(entry);
         }
-        g_free(entry);
     }
     trace_vnc_job_nrects(&vs, job, n_rectangles);
     vnc_unlock_display(job->vs->vd);
diff --git a/ui/vnc.c b/ui/vnc.c
index 9241caaad9..2e60b55e47 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -972,6 +972,9 @@  int vnc_send_framebuffer_update(VncState *vs, int x, int y, int w, int h)
         case VNC_ENCODING_ZYWRLE:
             n = vnc_zywrle_send_framebuffer_update(vs, x, y, w, h);
             break;
+        case VNC_ENCODING_H264:
+            n = vnc_h264_send_framebuffer_update(vs, x, y, w, h);
+            break;
         default:
             vnc_framebuffer_update(vs, x, y, w, h, VNC_ENCODING_RAW);
             n = vnc_raw_send_framebuffer_update(vs, x, y, w, h);
@@ -1326,6 +1329,10 @@  void vnc_disconnect_finish(VncState *vs)
     vnc_tight_clear(vs);
     vnc_zrle_clear(vs);
 
+#ifdef CONFIG_GSTREAMER
+    vnc_h264_clear(vs);
+#endif
+
 #ifdef CONFIG_VNC_SASL
     vnc_sasl_client_cleanup(vs);
 #endif /* CONFIG_VNC_SASL */
@@ -2181,6 +2188,16 @@  static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
             vnc_set_feature(vs, VNC_FEATURE_ZYWRLE);
             vs->vnc_encoding = enc;
             break;
+#ifdef CONFIG_GSTREAMER
+        case VNC_ENCODING_H264:
+            if (vnc_h264_encoder_init(vs) == 0) {
+                vnc_set_feature(vs, VNC_FEATURE_H264);
+                vs->vnc_encoding = enc;
+            } else {
+                VNC_DEBUG("vnc_h264_encoder_init failed\n");
+            }
+            break;
+#endif
         case VNC_ENCODING_DESKTOPRESIZE:
             vnc_set_feature(vs, VNC_FEATURE_RESIZE);
             break;
@@ -4291,6 +4308,10 @@  int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp)
     Error *local_err = NULL;
     char *id = (char *)qemu_opts_id(opts);
 
+#ifdef CONFIG_GSTREAMER
+    gst_init(NULL, NULL);
+#endif
+
     assert(id);
     vnc_display_init(id, &local_err);
     if (local_err) {
diff --git a/ui/vnc.h b/ui/vnc.h
index acc53a2cc1..7e232f7dac 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -46,6 +46,10 @@ 
 #include "vnc-enc-zrle.h"
 #include "ui/kbd-state.h"
 
+#ifdef CONFIG_GSTREAMER
+#include <gst/gst.h>
+#endif
+
 // #define _VNC_DEBUG 1
 
 #ifdef _VNC_DEBUG
@@ -231,6 +235,14 @@  typedef struct VncZywrle {
     int buf[VNC_ZRLE_TILE_WIDTH * VNC_ZRLE_TILE_HEIGHT];
 } VncZywrle;
 
+#ifdef CONFIG_GSTREAMER
+typedef struct VncH264 {
+    GstElement *pipeline, *source, *gst_encoder, *sink, *convert;
+    size_t width;
+    size_t height;
+} VncH264;
+#endif
+
 struct VncRect
 {
     int x;
@@ -344,6 +356,9 @@  struct VncState
     VncHextile hextile;
     VncZrle *zrle;
     VncZywrle zywrle;
+#ifdef CONFIG_GSTREAMER
+    VncH264 *h264;
+#endif
 
     Notifier mouse_mode_notifier;
 
@@ -404,6 +419,7 @@  enum {
 #define VNC_ENCODING_TRLE                 0x0000000f
 #define VNC_ENCODING_ZRLE                 0x00000010
 #define VNC_ENCODING_ZYWRLE               0x00000011
+#define VNC_ENCODING_H264                 0x00000032 /* 50   */
 #define VNC_ENCODING_COMPRESSLEVEL0       0xFFFFFF00 /* -256 */
 #define VNC_ENCODING_QUALITYLEVEL0        0xFFFFFFE0 /* -32  */
 #define VNC_ENCODING_XCURSOR              0xFFFFFF10 /* -240 */
@@ -464,6 +480,7 @@  enum VncFeatures {
     VNC_FEATURE_XVP,
     VNC_FEATURE_CLIPBOARD_EXT,
     VNC_FEATURE_AUDIO,
+    VNC_FEATURE_H264,
 };
 
 
@@ -625,6 +642,10 @@  int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
 int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
 void vnc_zrle_clear(VncState *vs);
 
+int vnc_h264_encoder_init(VncState *vs);
+int vnc_h264_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
+void vnc_h264_clear(VncState *vs);
+
 /* vnc-clipboard.c */
 void vnc_server_cut_text_caps(VncState *vs);
 void vnc_client_cut_text(VncState *vs, size_t len, uint8_t *text);