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jpegdec: don't allocate big arrays on the stack

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Add the arrays to the instance data and allocate on first use.
This commit is contained in:
Stefan Kost 2009-11-03 17:35:15 +02:00
parent 65a1db99eb
commit e3e910e971
2 changed files with 31 additions and 14 deletions

41
ext/jpeg/gstjpegdec.c
View file

@ -148,12 +148,19 @@ static void
gst_jpeg_dec_finalize (GObject * object)
{
GstJpegDec *dec = GST_JPEG_DEC (object);
gint i;
jpeg_destroy_decompress (&dec->cinfo);
if (dec->tempbuf)
gst_buffer_unref (dec->tempbuf);
for (i = 0; i < 16; i++) {
g_free (dec->idr_y[i]);
g_free (dec->idr_u[i]);
g_free (dec->idr_v[i]);
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
@ -679,20 +686,7 @@ static void
gst_jpeg_dec_decode_indirect (GstJpegDec * dec, guchar * base[3],
guchar * last[3], guint width, guint height, gint r_v, gint r_h)
{
/* FIXME: these are too large now that MAX_WIDTH is 64k! Allocating 3MB on
* the stack is not very nice... */
guchar y[16][MAX_WIDTH];
guchar u[16][MAX_WIDTH];
guchar v[16][MAX_WIDTH];
guchar *y_rows[16] = { y[0], y[1], y[2], y[3], y[4], y[5], y[6], y[7],
y[8], y[9], y[10], y[11], y[12], y[13], y[14], y[15]
};
guchar *u_rows[16] = { u[0], u[1], u[2], u[3], u[4], u[5], u[6], u[7],
u[8], u[9], u[10], u[11], u[12], u[13], u[14], u[15]
};
guchar *v_rows[16] = { v[0], v[1], v[2], v[3], v[4], v[5], v[6], v[7],
v[8], v[9], v[10], v[11], v[12], v[13], v[14], v[15]
};
guchar *y_rows[16], *u_rows[16], *v_rows[16];
guchar **scanarray[3] = { y_rows, u_rows, v_rows };
gint i, j, k;
gint lines;
@ -700,6 +694,25 @@ gst_jpeg_dec_decode_indirect (GstJpegDec * dec, guchar * base[3],
GST_DEBUG_OBJECT (dec,
"unadvantageous width or r_h, taking slow route involving memcpy");
if (G_UNLIKELY (!dec->idr_allocated)) {
gboolean res = TRUE;
for (i = 0; ((i < 16) && res); i++) {
res &= ((dec->idr_y[i] = g_try_malloc (MAX_WIDTH)) != NULL);
res &= ((dec->idr_u[i] = g_try_malloc (MAX_WIDTH)) != NULL);
res &= ((dec->idr_v[i] = g_try_malloc (MAX_WIDTH)) != NULL);
}
if (!res) {
GST_WARNING_OBJECT (dec, "out of memory");
return;
}
dec->idr_allocated = TRUE;
}
memcpy (y_rows, dec->idr_y, 16 * sizeof (gpointer));
memcpy (u_rows, dec->idr_u, 16 * sizeof (gpointer));
memcpy (v_rows, dec->idr_v, 16 * sizeof (gpointer));
for (i = 0; i < height; i += r_v * DCTSIZE) {
lines = jpeg_read_raw_data (&dec->cinfo, scanarray, r_v * DCTSIZE);
if (G_LIKELY (lines > 0)) {

4
ext/jpeg/gstjpegdec.h
View file

@ -106,6 +106,10 @@ struct _GstJpegDec {
struct jpeg_decompress_struct cinfo;
struct GstJpegDecErrorMgr jerr;
struct GstJpegDecSourceMgr jsrc;
/* arrays for indirect decoding */
gboolean idr_allocated;
guchar *idr_y[16],*idr_u[16],*idr_v[16];
};
struct _GstJpegDecClass {