gstreamer/subprojects/gst-plugins-base/gst-libs/gst/video/video-info-dma.c

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/* GStreamer
* Copyright (C) 2022 Intel Corporation
* Author: He Junyan <junyan.he@intel.com>
* Author: Liu Yinhang <yinhang.liu@intel.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:video-info-dma-drm
* @title: GstVideoInfoDmaDrm
* @short_description: Structures and enumerations to describe DMA video
* format in DRM mode.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "video-info-dma.h"
#include <gst/allocators/gstdmabuf.h>
/*
* To avoid header file dependency, some of the FOURCC and MODIFIER
* are copied here. All these values are const and will not changes.
* The full authoritative list of format modifier codes is found in
* `include/uapi/drm/drm_fourcc.h`
*/
#define fourcc_code(a, b, c, d) ((guint32)(a) | ((guint32)(b) << 8) | \
((guint32)(c) << 16) | ((guint32)(d) << 24))
/* Reserve 0 for the invalid format specifier */
#define DRM_FORMAT_INVALID 0
/* packed YCbCr */
#define DRM_FORMAT_YUYV fourcc_code('Y', 'U', 'Y', 'V') /* [31:0] Cr0:Y1:Cb0:Y0 8:8:8:8 little endian */
#define DRM_FORMAT_YVYU fourcc_code('Y', 'V', 'Y', 'U') /* [31:0] Cb0:Y1:Cr0:Y0 8:8:8:8 little endian */
#define DRM_FORMAT_UYVY fourcc_code('U', 'Y', 'V', 'Y') /* [31:0] Y1:Cr0:Y0:Cb0 8:8:8:8 little endian */
#define DRM_FORMAT_VYUY fourcc_code('V', 'Y', 'U', 'Y') /* [31:0] Y1:Cb0:Y0:Cr0 8:8:8:8 little endian */
#define DRM_FORMAT_AYUV fourcc_code('A', 'Y', 'U', 'V') /* [31:0] A:Y:Cb:Cr 8:8:8:8 little endian */
/*
* 2 plane YCbCr
* index 0 = Y plane, [7:0] Y
* index 1 = Cr:Cb plane, [15:0] Cr:Cb little endian
* or
* index 1 = Cb:Cr plane, [15:0] Cb:Cr little endian
*/
#define DRM_FORMAT_NV12 fourcc_code('N', 'V', '1', '2') /* 2x2 subsampled Cr:Cb plane */
#define DRM_FORMAT_NV21 fourcc_code('N', 'V', '2', '1') /* 2x2 subsampled Cb:Cr plane */
#define DRM_FORMAT_NV16 fourcc_code('N', 'V', '1', '6') /* 2x1 subsampled Cr:Cb plane */
#define DRM_FORMAT_NV61 fourcc_code('N', 'V', '6', '1') /* 2x1 subsampled Cb:Cr plane */
#define DRM_FORMAT_NV24 fourcc_code('N', 'V', '2', '4') /* non-subsampled Cr:Cb plane */
/*
* 3 plane YCbCr
* index 0: Y plane, [7:0] Y
* index 1: Cb plane, [7:0] Cb
* index 2: Cr plane, [7:0] Cr
* or
* index 1: Cr plane, [7:0] Cr
* index 2: Cb plane, [7:0] Cb
*/
#define DRM_FORMAT_YUV410 fourcc_code('Y', 'U', 'V', '9') /* 4x4 subsampled Cb (1) and Cr (2) planes */
#define DRM_FORMAT_YVU410 fourcc_code('Y', 'V', 'U', '9') /* 4x4 subsampled Cr (1) and Cb (2) planes */
#define DRM_FORMAT_YUV411 fourcc_code('Y', 'U', '1', '1') /* 4x1 subsampled Cb (1) and Cr (2) planes */
#define DRM_FORMAT_YUV420 fourcc_code('Y', 'U', '1', '2') /* 2x2 subsampled Cb (1) and Cr (2) planes */
#define DRM_FORMAT_YVU420 fourcc_code('Y', 'V', '1', '2') /* 2x2 subsampled Cr (1) and Cb (2) planes */
#define DRM_FORMAT_YUV422 fourcc_code('Y', 'U', '1', '6') /* 2x1 subsampled Cb (1) and Cr (2) planes */
#define DRM_FORMAT_YUV444 fourcc_code('Y', 'U', '2', '4') /* non-subsampled Cb (1) and Cr (2) planes */
/* 16 bpp RGB */
#define DRM_FORMAT_RGB565 fourcc_code('R', 'G', '1', '6') /* [15:0] R:G:B 5:6:5 little endian */
#define DRM_FORMAT_BGR565 fourcc_code('B', 'G', '1', '6') /* [15:0] B:G:R 5:6:5 little endian */
/* 32 bpp RGB */
#define DRM_FORMAT_ARGB8888 fourcc_code('A', 'R', '2', '4') /* [31:0] A:R:G:B 8:8:8:8 little endian */
#define DRM_FORMAT_ABGR8888 fourcc_code('A', 'B', '2', '4') /* [31:0] A:B:G:R 8:8:8:8 little endian */
#define DRM_FORMAT_RGBA8888 fourcc_code('R', 'A', '2', '4') /* [31:0] R:G:B:A 8:8:8:8 little endian */
#define DRM_FORMAT_BGRA8888 fourcc_code('B', 'A', '2', '4') /* [31:0] B:G:R:A 8:8:8:8 little endian */
#define DRM_FORMAT_XRGB8888 fourcc_code('X', 'R', '2', '4') /* [31:0] x:R:G:B 8:8:8:8 little endian */
#define DRM_FORMAT_XBGR8888 fourcc_code('X', 'B', '2', '4') /* [31:0] x:B:G:R 8:8:8:8 little endian */
#define DRM_FORMAT_RGBX8888 fourcc_code('R', 'X', '2', '4') /* [31:0] R:G:B:x 8:8:8:8 little endian */
#define DRM_FORMAT_BGRX8888 fourcc_code('B', 'X', '2', '4') /* [31:0] B:G:R:x 8:8:8:8 little endian */
/*
* Linear Layout
*
* Just plain linear layout. Note that this is different from no specifying any
* modifier (e.g. not setting DRM_MODE_FB_MODIFIERS in the DRM_ADDFB2 ioctl),
* which tells the driver to also take driver-internal information into account
* and so might actually result in a tiled framebuffer.
*/
#define DRM_FORMAT_MOD_LINEAR 0ULL
/*
* Invalid Modifier
*
* This modifier can be used as a sentinel to terminate the format modifiers
* list, or to initialize a variable with an invalid modifier. It might also be
* used to report an error back to userspace for certain APIs.
*/
#define DRM_FORMAT_MOD_INVALID 0xffffffffffffff
#ifndef GST_DISABLE_GST_DEBUG
#define GST_CAT_DEFAULT ensure_debug_category()
static GstDebugCategory *
ensure_debug_category (void)
{
static gsize cat_gonce = 0;
if (g_once_init_enter (&cat_gonce)) {
gsize cat_done;
cat_done = (gsize) _gst_debug_category_new ("video-info-dma-drm", 0,
"video-info-dma-drm structure");
g_once_init_leave (&cat_gonce, cat_done);
}
return (GstDebugCategory *) cat_gonce;
}
#else
#define ensure_debug_category() /* NOOP */
#endif /* GST_DISABLE_GST_DEBUG */
static GstVideoInfoDmaDrm *
gst_video_info_dma_drm_copy (const GstVideoInfoDmaDrm * drm_info)
{
return g_memdup2 (drm_info, sizeof (GstVideoInfoDmaDrm));
}
/**
* gst_video_info_dma_drm_free:
* @drm_info: a #GstVideoInfoDmaDrm
*
* Free a #GstVideoInfoDmaDrm structure previously allocated with
* gst_video_info_dma_drm_new()
*
* Since: 1.24
*/
void
gst_video_info_dma_drm_free (GstVideoInfoDmaDrm * drm_info)
{
g_free (drm_info);
}
G_DEFINE_BOXED_TYPE (GstVideoInfoDmaDrm, gst_video_info_dma_drm,
(GBoxedCopyFunc) gst_video_info_dma_drm_copy,
(GBoxedFreeFunc) gst_video_info_dma_drm_free);
/**
* gst_video_info_dma_drm_init:
* @drm_info: (out caller-allocates): a #GstVideoInfoDmaDrm
*
* Initialize @drm_info with default values.
*
* Since: 1.24
*/
void
gst_video_info_dma_drm_init (GstVideoInfoDmaDrm * drm_info)
{
g_return_if_fail (drm_info != NULL);
gst_video_info_init (&drm_info->vinfo);
drm_info->drm_fourcc = DRM_FORMAT_INVALID;
drm_info->drm_modifier = DRM_FORMAT_MOD_INVALID;
}
/**
* gst_video_info_dma_drm_new:
*
* Allocate a new #GstVideoInfoDmaDrm that is also initialized with
* gst_video_info_dma_drm_init().
*
* Returns: (transfer full): a new #GstVideoInfoDmaDrm.
* Free it with gst_video_info_dma_drm_free().
*
* Since: 1.24
*/
GstVideoInfoDmaDrm *
gst_video_info_dma_drm_new (void)
{
GstVideoInfoDmaDrm *info;
info = g_new (GstVideoInfoDmaDrm, 1);
gst_video_info_dma_drm_init (info);
return info;
}
/**
* gst_video_is_dma_drm_caps:
* @caps: a #GstCaps
*
* Check whether the @caps is a dma drm kind caps. Please note that
* the caps should be fixed.
*
* Returns: %TRUE if the caps is a dma drm caps.
*
* Since: 1.24
*/
gboolean
gst_video_is_dma_drm_caps (const GstCaps * caps)
{
GstStructure *structure;
g_return_val_if_fail (caps != NULL, FALSE);
if (!gst_caps_is_fixed (caps))
return FALSE;
if (!gst_caps_features_contains (gst_caps_get_features (caps, 0),
GST_CAPS_FEATURE_MEMORY_DMABUF))
return FALSE;
structure = gst_caps_get_structure (caps, 0);
if (gst_structure_has_field (structure, "format"))
return FALSE;
return TRUE;
}
/**
* gst_video_info_dma_drm_to_caps:
* @drm_info: a #GstVideoInfoDmaDrm
*
* Convert the values of @drm_info into a #GstCaps. Please note that the
* @caps returned will be a dma drm caps which does not contain format field,
* but contains a drm-format field instead. The value of drm-format field is
* composed of a drm fourcc and a modifier, such as NV12:0x0100000000000002.
*
* Returns: (transfer full) (nullable): a new #GstCaps containing the
* info in @drm_info.
*
* Since: 1.24
*/
GstCaps *
gst_video_info_dma_drm_to_caps (const GstVideoInfoDmaDrm * drm_info)
{
GstCaps *caps;
GstStructure *structure;
gchar *str;
g_return_val_if_fail (drm_info != NULL, NULL);
g_return_val_if_fail (drm_info->drm_fourcc != DRM_FORMAT_INVALID, NULL);
g_return_val_if_fail (drm_info->drm_modifier != DRM_FORMAT_MOD_INVALID, NULL);
caps = gst_video_info_to_caps (&drm_info->vinfo);
if (!caps) {
GST_DEBUG ("Failed to create caps from video info");
return NULL;
}
str = gst_video_dma_drm_fourcc_to_string (drm_info->drm_fourcc,
drm_info->drm_modifier);
structure = gst_caps_get_structure (caps, 0);
gst_structure_remove_field (structure, "format");
gst_structure_set (structure, "drm-format", G_TYPE_STRING, str, NULL);
g_free (str);
return caps;
}
/**
* gst_video_info_dma_drm_from_caps:
* @drm_info: (out caller-allocates): #GstVideoInfoDmaDrm
* @caps: a #GstCaps
*
* Parse @caps and update @info. Please note that the @caps should be
* a dma drm caps. The gst_video_is_dma_drm_caps() can be used to verify
* it before calling this function.
*
* Returns: TRUE if @caps could be parsed
*
* Since: 1.24
*/
gboolean
gst_video_info_dma_drm_from_caps (GstVideoInfoDmaDrm * drm_info,
const GstCaps * caps)
{
GstStructure *structure;
const gchar *str;
guint32 fourcc;
guint64 modifier;
GstVideoFormat format;
GstCaps *tmp_caps = NULL;
gboolean ret;
g_return_val_if_fail (drm_info != NULL, FALSE);
g_return_val_if_fail (caps != NULL, FALSE);
if (!gst_video_is_dma_drm_caps (caps))
return FALSE;
GST_DEBUG ("parsing caps %" GST_PTR_FORMAT, caps);
tmp_caps = gst_caps_copy (caps);
structure = gst_caps_get_structure (tmp_caps, 0);
str = gst_structure_get_string (structure, "drm-format");
if (!str) {
GST_DEBUG ("drm caps %" GST_PTR_FORMAT "has no drm-format field", caps);
ret = FALSE;
goto out;
}
fourcc = gst_video_dma_drm_fourcc_from_string (str, &modifier);
if (fourcc == DRM_FORMAT_INVALID) {
GST_DEBUG ("Can not parse fourcc in caps %" GST_PTR_FORMAT, caps);
ret = FALSE;
goto out;
}
if (modifier == DRM_FORMAT_MOD_INVALID) {
GST_DEBUG ("Can not parse modifier in caps %" GST_PTR_FORMAT, caps);
ret = FALSE;
goto out;
}
/* If the modifier is linear, set the according format in video info,
* otherwise, just set the format to GST_VIDEO_FORMAT_ENCODED. */
/* TODO: Some well known tiled format such as NV12_4L4, NV12_16L16,
* NV12_64Z32, NV12_16L32S */
format = gst_video_dma_drm_fourcc_to_format (fourcc);
if (modifier == DRM_FORMAT_MOD_LINEAR && format != GST_VIDEO_FORMAT_UNKNOWN) {
gst_structure_set (structure, "format", G_TYPE_STRING,
gst_video_format_to_string (format), NULL);
} else {
gst_structure_set (structure, "format", G_TYPE_STRING,
gst_video_format_to_string (GST_VIDEO_FORMAT_ENCODED), NULL);
}
gst_structure_remove_field (structure, "drm-format");
if (!gst_video_info_from_caps (&drm_info->vinfo, tmp_caps)) {
GST_DEBUG ("Can not parse video info for caps %" GST_PTR_FORMAT, tmp_caps);
ret = FALSE;
goto out;
}
drm_info->drm_fourcc = fourcc;
drm_info->drm_modifier = modifier;
ret = TRUE;
out:
gst_clear_caps (&tmp_caps);
return ret;
}
/**
* gst_video_info_dma_drm_new_from_caps:
* @caps: a #GstCaps
*
* Parse @caps to generate a #GstVideoInfoDmaDrm. Please note that the
* @caps should be a dma drm caps. The gst_video_is_dma_drm_caps() can
* be used to verify it before calling this function.
*
* Returns: (transfer full) (nullable): A #GstVideoInfoDmaDrm,
* or %NULL if @caps couldn't be parsed.
*
* Since: 1.24
*/
GstVideoInfoDmaDrm *
gst_video_info_dma_drm_new_from_caps (const GstCaps * caps)
{
GstVideoInfoDmaDrm *ret;
g_return_val_if_fail (caps != NULL, NULL);
if (!gst_video_is_dma_drm_caps (caps))
return NULL;
ret = gst_video_info_dma_drm_new ();
if (gst_video_info_dma_drm_from_caps (ret, caps)) {
return ret;
} else {
gst_video_info_dma_drm_free (ret);
return NULL;
}
}
/**
* gst_video_info_dma_drm_from_video_info:
* @drm_info: (out caller-allocates): #GstVideoInfoDmaDrm
* @info: a #GstVideoInfo
* @modifier: the associated modifier value.
*
* Fills @drm_info if @info's format has a valid drm format and @modifier is also
* valid
*
* Returns: %TRUE if @drm_info is filled correctly.
*
* Since: 1.24
*/
gboolean
gst_video_info_dma_drm_from_video_info (GstVideoInfoDmaDrm * drm_info,
const GstVideoInfo * info, guint64 modifier)
{
GstVideoFormat format;
guint32 fourcc;
g_return_val_if_fail (drm_info != NULL, FALSE);
g_return_val_if_fail (info != NULL, FALSE);
if (modifier == DRM_FORMAT_MOD_INVALID)
return FALSE;
format = GST_VIDEO_INFO_FORMAT (info);
fourcc = gst_video_dma_drm_fourcc_from_format (format);
if (fourcc == DRM_FORMAT_INVALID)
return FALSE;
drm_info->vinfo = *info;
drm_info->drm_fourcc = fourcc;
drm_info->drm_modifier = modifier;
/* no need to change format to GST_VIDEO_INFO_ENCODED since its modifier is
* linear */
if (modifier == DRM_FORMAT_MOD_LINEAR)
return TRUE;
return gst_video_info_set_interlaced_format (&drm_info->vinfo,
GST_VIDEO_FORMAT_ENCODED, GST_VIDEO_INFO_INTERLACE_MODE (info),
GST_VIDEO_INFO_WIDTH (info), GST_VIDEO_INFO_HEIGHT (info));
}
/**
* gst_video_dma_drm_fourcc_from_string:
* @format_str: a drm format string
* @modifier: (out) (optional): Return the modifier in @format or %NULL
* to ignore.
*
* Convert the @format_str string into the drm fourcc value. The @modifier is
* also parsed if we want. Please note that the @format_str should follow the
* fourcc:modifier kind style, such as NV12:0x0100000000000002
*
* Returns: The drm fourcc value or DRM_FORMAT_INVALID if @format_str is
* invalid.
*
* Since: 1.24
*/
guint32
gst_video_dma_drm_fourcc_from_string (const gchar * format_str,
guint64 * modifier)
{
const gchar *mod_str;
guint32 fourcc = DRM_FORMAT_INVALID;
guint64 m = DRM_FORMAT_MOD_INVALID;
g_return_val_if_fail (format_str != NULL, 0);
mod_str = strchr (format_str, ':');
if (mod_str) {
if (mod_str - format_str != 4) {
/* fourcc always has 4 characters. */
GST_DEBUG ("%s is not a drm string", format_str);
return DRM_FORMAT_INVALID;
}
mod_str++;
/* modifier should in hex mode. */
if (!(mod_str[0] == '0' && (mod_str[1] == 'X' || mod_str[1] == 'x'))) {
GST_DEBUG ("Invalid modifier string");
return DRM_FORMAT_INVALID;
}
m = g_ascii_strtoull (mod_str, NULL, 16);
if (m == DRM_FORMAT_MOD_LINEAR) {
GST_DEBUG ("Unrecognized modifier string %s", mod_str);
return DRM_FORMAT_INVALID;
}
} else {
if (strlen (format_str) != 4) {
/* fourcc always has 4 characters. */
GST_DEBUG ("%s is not a drm string", format_str);
return DRM_FORMAT_INVALID;
}
m = DRM_FORMAT_MOD_LINEAR;
}
fourcc = GST_MAKE_FOURCC (format_str[0], format_str[1],
format_str[2], format_str[3]);
if (modifier)
*modifier = m;
return fourcc;
}
/**
* gst_video_dma_drm_fourcc_to_string:
* @fourcc: a drm fourcc value.
* @modifier: the associated modifier value.
*
* Returns a string containing drm kind format, such as
* NV12:0x0100000000000002, or NULL otherwise.
*
* Returns: (transfer full) (nullable): the drm kind string composed
* of to @fourcc and @modifier.
*
* Since: 1.24
*/
gchar *
gst_video_dma_drm_fourcc_to_string (guint32 fourcc, guint64 modifier)
{
gchar *s;
g_return_val_if_fail (fourcc != DRM_FORMAT_INVALID, NULL);
g_return_val_if_fail (modifier != DRM_FORMAT_MOD_INVALID, NULL);
if (modifier == DRM_FORMAT_MOD_LINEAR) {
s = g_strdup_printf ("%" GST_FOURCC_FORMAT, GST_FOURCC_ARGS (fourcc));
} else {
s = g_strdup_printf ("%" GST_FOURCC_FORMAT ":0x%016" G_GINT64_MODIFIER "x",
GST_FOURCC_ARGS (fourcc), modifier);
}
return s;
}
/* *INDENT-OFF* */
static const struct FormatMap
{
GstVideoFormat format;
guint32 fourcc;
} format_map[] = {
{GST_VIDEO_FORMAT_YUY2, DRM_FORMAT_YUYV},
{GST_VIDEO_FORMAT_YVYU, DRM_FORMAT_YVYU},
{GST_VIDEO_FORMAT_UYVY, DRM_FORMAT_UYVY},
{GST_VIDEO_FORMAT_VYUY, DRM_FORMAT_VYUY},
/* No VUYA fourcc define, just mapping it as AYUV. */
{GST_VIDEO_FORMAT_VUYA, DRM_FORMAT_AYUV},
{GST_VIDEO_FORMAT_NV12, DRM_FORMAT_NV12},
{GST_VIDEO_FORMAT_NV21, DRM_FORMAT_NV21},
{GST_VIDEO_FORMAT_NV16, DRM_FORMAT_NV16},
{GST_VIDEO_FORMAT_NV61, DRM_FORMAT_NV61},
{GST_VIDEO_FORMAT_NV24, DRM_FORMAT_NV24},
{GST_VIDEO_FORMAT_YUV9, DRM_FORMAT_YUV410},
{GST_VIDEO_FORMAT_YVU9, DRM_FORMAT_YVU410},
{GST_VIDEO_FORMAT_Y41B, DRM_FORMAT_YUV411},
{GST_VIDEO_FORMAT_I420, DRM_FORMAT_YUV420},
{GST_VIDEO_FORMAT_YV12, DRM_FORMAT_YVU420},
{GST_VIDEO_FORMAT_Y42B, DRM_FORMAT_YUV422},
{GST_VIDEO_FORMAT_Y444, DRM_FORMAT_YUV444},
{GST_VIDEO_FORMAT_RGB16, DRM_FORMAT_RGB565},
{GST_VIDEO_FORMAT_BGR16, DRM_FORMAT_BGR565},
{GST_VIDEO_FORMAT_RGBA, DRM_FORMAT_ABGR8888},
{GST_VIDEO_FORMAT_RGBx, DRM_FORMAT_XBGR8888},
{GST_VIDEO_FORMAT_BGRA, DRM_FORMAT_ARGB8888},
{GST_VIDEO_FORMAT_BGRx, DRM_FORMAT_XRGB8888},
{GST_VIDEO_FORMAT_ARGB, DRM_FORMAT_BGRA8888},
{GST_VIDEO_FORMAT_xRGB, DRM_FORMAT_BGRX8888},
{GST_VIDEO_FORMAT_ABGR, DRM_FORMAT_RGBA8888},
{GST_VIDEO_FORMAT_xBGR, DRM_FORMAT_RGBX8888},
};
/* *INDENT-ON* */
/**
* gst_video_dma_drm_fourcc_from_format:
* @format: a #GstVideoFormat
*
* Converting the video format into dma drm fourcc. If no
* matching fourcc found, then DRM_FORMAT_INVALID is returned.
*
* Returns: the DRM_FORMAT_* corresponding to the @format.
*
* Since: 1.24
*/
guint32
gst_video_dma_drm_fourcc_from_format (GstVideoFormat format)
{
guint i;
for (i = 0; i < G_N_ELEMENTS (format_map); i++) {
if (format_map[i].format == format)
return format_map[i].fourcc;
}
GST_INFO ("No supported fourcc for video format %s",
gst_video_format_to_string (format));
return DRM_FORMAT_INVALID;
}
/**
* gst_video_dma_drm_fourcc_to_format:
* @fourcc: the dma drm value.
*
* Converting a dma drm fourcc into the video format. If no matching
* video format found, then GST_VIDEO_FORMAT_UNKNOWN is returned.
*
* Returns: the GST_VIDEO_FORMAT_* corresponding to the @fourcc.
*
* Since: 1.24
*/
GstVideoFormat
gst_video_dma_drm_fourcc_to_format (guint32 fourcc)
{
guint i;
for (i = 0; i < G_N_ELEMENTS (format_map); i++) {
if (format_map[i].fourcc == fourcc)
return format_map[i].format;
}
GST_INFO ("No supported video format for fourcc %" GST_FOURCC_FORMAT,
GST_FOURCC_ARGS (fourcc));
return GST_VIDEO_FORMAT_UNKNOWN;
}