[FFmpeg-devel] [PATCH 1/3 v9] avformat: add a Tile Grid stream group type
James Almer
jamrial at gmail.com
Sat Feb 10 00:28:15 EET 2024
This will be used to support tiled image formats like HEIF.
Signed-off-by: James Almer <jamrial at gmail.com>
---
Changed the API to support overlaping tiles, as well as leaving pixels
unfilled. This allows us to implement Image Overlay HEIF support.
libavformat/avformat.c | 5 ++
libavformat/avformat.h | 127 +++++++++++++++++++++++++++++++++++++++++
libavformat/dump.c | 29 ++++++++++
libavformat/options.c | 34 +++++++++++
4 files changed, 195 insertions(+)
diff --git a/libavformat/avformat.c b/libavformat/avformat.c
index ca31d3dc56..f53ba4ce58 100644
--- a/libavformat/avformat.c
+++ b/libavformat/avformat.c
@@ -99,6 +99,11 @@ void ff_free_stream_group(AVStreamGroup **pstg)
av_iamf_mix_presentation_free(&stg->params.iamf_mix_presentation);
break;
}
+ case AV_STREAM_GROUP_PARAMS_TILE_GRID:
+ av_opt_free(stg->params.tile_grid);
+ av_freep(&stg->params.tile_grid->offsets);
+ av_freep(&stg->params.tile_grid);
+ break;
default:
break;
}
diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 5d0fe82250..97f68531ac 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1018,10 +1018,136 @@ typedef struct AVStream {
int pts_wrap_bits;
} AVStream;
+/**
+ * AVStreamGroupTileGrid holds information on how to combine several
+ * independent images on a single canvas for presentation.
+ *
+ * The following is an example of a simple grid with 3 rows and 4 columns:
+ *
+ * +---+---+---+---+
+ * | 0 | 1 | 2 | 3 |
+ * +---+---+---+---+
+ * | 4 | 5 | 6 | 7 |
+ * +---+---+---+---+
+ * | 8 | 9 |10 |11 |
+ * +---+---+---+---+
+ *
+ * Assuming all tiles have a dimension of 512x512, the
+ * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
+ * the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the
+ * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
+ * the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the
+ * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
+ * the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the
+ * @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of
+ * the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512",
+ * etc.
+ *
+ * The following is an example of a canvas with overlaping tiles:
+ *
+ * +---------------+
+ * |***** |
+ * |* 0##### |
+ * |***# 1 # |
+ * | ##### |
+ * | |
+ * | |
+ * | |
+ * +---------------+
+ *
+ * Assuming a canvas with size 2048x2048 and both tiles with a dimension of
+ * 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the
+ * topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group
+ * would be 256x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for
+ * the topleft pixel of the second @ref AVStreamGroup.streams "stream" in the
+ * group would be 512x512.
+ *
+ * sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be
+ * allocated by avformat_stream_group_create().
+ */
+typedef struct AVStreamGroupTileGrid {
+ const AVClass *av_class;
+
+ /**
+ * Width of the canvas.
+ *
+ * Must be > 0.
+ */
+ int coded_width;
+ /**
+ * Width of the canvas.
+ *
+ * Must be > 0.
+ */
+ int coded_height;
+
+ /**
+ * An @ref AVStreamGroup.nb_streams "nb_streams" sized array of offsets in
+ * pixels from the topleft edge of the canvas, indicating where each stream
+ * should be placed.
+ * It must be allocated with the av_malloc() family of functions.
+ *
+ * - demuxing: set by libavformat, must not be modified by the caller.
+ * - muxing: set by the caller before avformat_write_header().
+ *
+ * Freed by libavformat in avformat_free_context().
+ */
+ struct {
+ int x;
+ int y;
+ } *offsets;
+
+ /**
+ * The pixel value per channel in RGBA format used if no pixel of any tile
+ * is located at a particular pixel location.
+ *
+ * @see av_image_fill_color().
+ * @see av_parse_color().
+ */
+ uint8_t background[4];
+
+ /**
+ * Offset in pixels from the left edge of the canvas where the actual image
+ * meant for presentation starts.
+ *
+ * This field must be >= 0 and <= @ref coded_width.
+ */
+ int horizontal_offset;
+ /**
+ * Offset in pixels from the top edge of the canvas where the actual image
+ * meant for presentation starts.
+ *
+ * This field must be >= 0 and <= @ref coded_height.
+ */
+ int vertical_offset;
+
+ /**
+ * Width of the final image for presentation.
+ *
+ * Must be > 0 and <= (@ref coded_width - @ref horizontal_offset).
+ * When it's not equal to (@ref coded_width - @ref horizontal_offset), the
+ * result of (@ref coded_width - width - @ref horizontal_offset) is the
+ * amount amount of pixels to be cropped from the right edge of the
+ * final image before presentation.
+ */
+ int width;
+ /**
+ * Height of the final image for presentation.
+ *
+ * Must be > 0 and <= (@ref coded_height - @ref vertical_offset).
+ * When it's not equal to (@ref coded_height - @ref vertical_offset), the
+ * result of (@ref coded_height - height - @ref vertical_offset) is the
+ * amount amount of pixels to be cropped from the bottom edge of the
+ * final image before presentation.
+ */
+ int height;
+} AVStreamGroupTileGrid;
+
enum AVStreamGroupParamsType {
AV_STREAM_GROUP_PARAMS_NONE,
AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT,
AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION,
+ AV_STREAM_GROUP_PARAMS_TILE_GRID,
};
struct AVIAMFAudioElement;
@@ -1062,6 +1188,7 @@ typedef struct AVStreamGroup {
union {
struct AVIAMFAudioElement *iamf_audio_element;
struct AVIAMFMixPresentation *iamf_mix_presentation;
+ struct AVStreamGroupTileGrid *tile_grid;
} params;
/**
diff --git a/libavformat/dump.c b/libavformat/dump.c
index 9d37179bb7..756db8c87e 100644
--- a/libavformat/dump.c
+++ b/libavformat/dump.c
@@ -22,6 +22,7 @@
#include <stdio.h>
#include <stdint.h>
+#include "libavutil/avstring.h"
#include "libavutil/channel_layout.h"
#include "libavutil/display.h"
#include "libavutil/iamf.h"
@@ -738,6 +739,34 @@ static void dump_stream_group(const AVFormatContext *ic, uint8_t *printed,
}
break;
}
+ case AV_STREAM_GROUP_PARAMS_TILE_GRID: {
+ const AVStreamGroupTileGrid *tile_grid = stg->params.tile_grid;
+ AVCodecContext *avctx = avcodec_alloc_context3(NULL);
+ const char *ptr = NULL;
+ av_log(NULL, AV_LOG_INFO, " Tile Grid:");
+ if (avctx && stg->nb_streams && !avcodec_parameters_to_context(avctx, stg->streams[0]->codecpar)) {
+ avctx->width = tile_grid->width;
+ avctx->height = tile_grid->height;
+ avctx->coded_width = tile_grid->coded_width;
+ avctx->coded_height = tile_grid->coded_height;
+ if (ic->dump_separator)
+ av_opt_set(avctx, "dump_separator", ic->dump_separator, 0);
+ buf[0] = 0;
+ avcodec_string(buf, sizeof(buf), avctx, is_output);
+ ptr = av_stristr(buf, " ");
+ }
+ avcodec_free_context(&avctx);
+ if (ptr)
+ av_log(NULL, AV_LOG_INFO, "%s", ptr);
+ av_log(NULL, AV_LOG_INFO, "\n");
+ dump_metadata(NULL, stg->metadata, " ", AV_LOG_INFO);
+ for (int i = 0; i < stg->nb_streams; i++) {
+ const AVStream *st = stg->streams[i];
+ dump_stream_format(ic, st->index, i, index, is_output, AV_LOG_VERBOSE);
+ printed[st->index] = 1;
+ }
+ break;
+ }
default:
break;
}
diff --git a/libavformat/options.c b/libavformat/options.c
index 03e6a2a7ff..a323aa7fe6 100644
--- a/libavformat/options.c
+++ b/libavformat/options.c
@@ -339,6 +339,28 @@ fail:
return NULL;
}
+#define FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM
+#define OFFSET(x) offsetof(AVStreamGroupTileGrid, x)
+static const AVOption tile_grid_options[] = {
+ { "grid_size", "size of the output canvas", OFFSET(coded_width),
+ AV_OPT_TYPE_IMAGE_SIZE, { .str = NULL }, 0, INT_MAX, FLAGS },
+ { "output_size", "size of valid pixels in output image meant for presentation", OFFSET(width),
+ AV_OPT_TYPE_IMAGE_SIZE, { .str = NULL }, 0, INT_MAX, FLAGS },
+ { "background_color", "set a background color for unused pixels",
+ OFFSET(background), AV_OPT_TYPE_COLOR, { .str = "black"}, 0, 0, FLAGS },
+ { "horizontal_offset", NULL, OFFSET(horizontal_offset), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
+ { "vertical_offset", NULL, OFFSET(vertical_offset), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
+ { NULL },
+};
+#undef FLAGS
+#undef OFFSET
+
+static const AVClass tile_grid_class = {
+ .class_name = "AVStreamGroupTileGrid",
+ .version = LIBAVUTIL_VERSION_INT,
+ .option = tile_grid_options,
+};
+
static void *stream_group_child_next(void *obj, void *prev)
{
AVStreamGroup *stg = obj;
@@ -348,6 +370,8 @@ static void *stream_group_child_next(void *obj, void *prev)
return stg->params.iamf_audio_element;
case AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION:
return stg->params.iamf_mix_presentation;
+ case AV_STREAM_GROUP_PARAMS_TILE_GRID:
+ return stg->params.tile_grid;
default:
break;
}
@@ -370,6 +394,9 @@ static const AVClass *stream_group_child_iterate(void **opaque)
case AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION:
ret = av_iamf_mix_presentation_get_class();
break;
+ case AV_STREAM_GROUP_PARAMS_TILE_GRID:
+ ret = &tile_grid_class;
+ break;
default:
break;
}
@@ -431,6 +458,13 @@ AVStreamGroup *avformat_stream_group_create(AVFormatContext *s,
if (!stg->params.iamf_mix_presentation)
goto fail;
break;
+ case AV_STREAM_GROUP_PARAMS_TILE_GRID:
+ stg->params.tile_grid = av_mallocz(sizeof(*stg->params.tile_grid));
+ if (!stg->params.tile_grid)
+ goto fail;
+ stg->params.tile_grid->av_class = &tile_grid_class;
+ av_opt_set_defaults(stg->params.tile_grid);
+ break;
default:
goto fail;
}
--
2.43.0
More information about the ffmpeg-devel
mailing list