p
/
fiv
1
1
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Fix GIF decoding for certain files 

The handling is not perfect yet, but it should be fine enough.
This commit is contained in:
Přemysl Eric Janouch 2022-01-08 05:32:42 +01:00
parent 231b77e6c0
commit b973d323ba
Signed by: p
GPG Key ID: A0420B94F92B9493
1 changed files with 13 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
fiv-io.c
View File

@ -564,10 +564,17 @@ load_wuffs_frame(struct load_wuffs_frame_context *ctx, GError **error)
return false;
}
// Wuffs' test/data/animated-red-blue.gif, e.g., needs this handling.
cairo_format_t decode_format = ctx->cairo_format;
if (wuffs_base__frame_config__index(&fc) > 0 &&
wuffs_base__pixel_config__pixel_format(&ctx->cfg.pixcfg).repr ==
WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL)
decode_format = CAIRO_FORMAT_ARGB32;
bool success = false;
unsigned char *targetbuf = NULL;
cairo_surface_t *surface =
cairo_image_surface_create(ctx->cairo_format, ctx->width, ctx->height);
cairo_image_surface_create(decode_format, ctx->width, ctx->height);
cairo_status_t surface_status = cairo_surface_status(surface);
if (surface_status != CAIRO_STATUS_SUCCESS) {
set_error(error, cairo_status_to_string(surface_status));
@ -659,6 +666,7 @@ load_wuffs_frame(struct load_wuffs_frame_context *ctx, GError **error)
cairo_surface_mark_dirty(canvas);
// Apply that frame's disposal method.
// XXX: We do not expect opaque pictures to receive holes this way.
wuffs_base__rect_ie_u32 bounds =
wuffs_base__frame_config__bounds(&ctx->last_fc);
// TODO(p): This field needs to be colour-managed.
@ -686,6 +694,8 @@ load_wuffs_frame(struct load_wuffs_frame_context *ctx, GError **error)
// TODO(p): Implement, it seems tricky.
// Might need another surface to keep track of the state.
break;
case WUFFS_BASE__ANIMATION_DISPOSAL__NONE:
break;
}
// Paint the current frame over that, within its bounds.
@ -844,8 +854,6 @@ open_wuffs(wuffs_base__image_decoder *dec, wuffs_base__io_buffer src,
// Wuffs maps tRNS to BGRA in `decoder.decode_trns?`, we should be fine.
// wuffs_base__pixel_format__transparency() doesn't reflect the image file.
// TODO(p): See if wuffs_base__image_config__first_frame_is_opaque() causes
// issues with animations, and eventually ensure an alpha-capable format.
bool opaque = wuffs_base__image_config__first_frame_is_opaque(&ctx.cfg);
// Wuffs' API is kind of awful--we want to catch wide RGB and wide grey.
@ -886,6 +894,8 @@ open_wuffs(wuffs_base__image_decoder *dec, wuffs_base__io_buffer src,
ctx.cairo_format = CAIRO_FORMAT_RGB30;
} else if (opaque) {
// BGRX doesn't have as wide swizzler support, namely in GIF.
// Moreover, follower frames may still be partly transparent.
// Therefore, we choose to keep "wuffs_format" intact.
ctx.cairo_format = CAIRO_FORMAT_RGB24;
} else if (!ctx.target) {
wuffs_format = WUFFS_BASE__PIXEL_FORMAT__BGRA_PREMUL;