#define HDR_LEN 12
+/* States for image readout */
+enum {
+ READ_STATE_INIT,
+ READ_STATE_HEADER,
+ READ_STATE_DATA,
+ READ_STATE_DONE,
+};
+
struct lbx_image_priv {
struct lbx_image pub;
long paloff;
- int currentframe;
- int currentx, currenty;
- unsigned char **framedata;
- unsigned char **mask;
+ /* State of frame readout */
+ unsigned currentx, currenty, currentn;
+ int read_state;
unsigned long offsets[];
};
.pub.leadin = hdr[8],
.pub.chunk = hdr[9],
.flags = unpack_16_le(hdr+10),
-
- .currentframe = -1,
};
if (img->flags & FLAG_OVERWRITE)
return lbx_img_open(p, &lbx_pipe_fops, pipe_close);
}
-static int _lbx_drawrow(struct lbx_image_priv *img)
+int lbx_img_seek(struct lbx_image *pub, unsigned frame)
{
- unsigned short length, offset;
- unsigned char buf[4];
- unsigned char *pos;
- size_t rc;
-
- assert(img->framedata);
- assert(img->mask);
-
- if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf)
- goto readerr;
-
- length = unpack_16_le(buf+0);
- offset = unpack_16_le(buf+2);
- if (length == 0 && offset == 1000)
- return 1;
-
- /* Length of 0 increments Y position */
- if (!length) {
- if (offset > img->pub.height - img->currenty) {
- lbx_error_raise(LBX_EFORMAT);
- return -1;
- }
-
- img->currenty += offset;
- img->currentx = 0;
- return 0;
- }
+ struct lbx_image_priv *img = (struct lbx_image_priv *)pub;
- /* Otherwise we read pixel data */
- if (offset > img->pub.width - img->currentx) {
- lbx_error_raise(LBX_EFORMAT);
+ if (frame >= pub->frames) {
+ lbx_error_raise(LBX_EINVAL);
return -1;
}
- img->currentx += offset;
- if (length > img->pub.width - img->currentx) {
- lbx_error_raise(LBX_EFORMAT);
+ if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) {
return -1;
}
- memset(&img->mask[img->currenty][img->currentx], 1, length);
+ if (!(img->flags & FLAG_RAW)) {
+ unsigned char buf[4];
- pos = &img->framedata[img->currenty][img->currentx];
- rc = img->fops->read(pos, length, img->f);
- img->currentx += rc;
+ /* Read frame header */
+ if (img->fops->read(buf, 4, img->f) != 4) {
+ if (img->fops->eof(img->f))
+ lbx_error_raise(LBX_EEOF);
+ return -1;
+ }
- if (rc < length)
- goto readerr;
+ if (unpack_16_le(buf) != 1) {
+ lbx_error_raise(LBX_EFORMAT);
+ return -1;
+ }
- /* Skip padding byte, if any */
- if (length % 2) {
- if (img->fops->read(buf, 1, img->f) != 1)
- goto readerr;
+ img->currentx = 0;
+ img->currenty = unpack_16_le(buf+2);
+ if (img->currenty > img->pub.height) {
+ lbx_error_raise(LBX_EFORMAT);
+ return -1;
+ }
}
+ img->read_state = READ_STATE_HEADER;
return 0;
-readerr:
- if (img->fops->eof(img->f))
- lbx_error_raise(LBX_EEOF);
- return -1;
}
-static unsigned char **allocframebuffer(size_t width, size_t height)
+long lbx_img_read_row_header(struct lbx_image *pub, unsigned *x, unsigned *y)
{
- unsigned char **new, *tmp;
- size_t i;
-
- if (height > SIZE_MAX / sizeof *new) {
- lbx_error_raise(LBX_ENOMEM);
- return NULL;
- }
-
- /* Ensure that there is at least one row in the framebuffer. */
- if (height == 0 || width == 0)
- width = height = 1;
-
- tmp = calloc(height, width);
- if (!tmp) {
- lbx_error_raise(LBX_ENOMEM);
- return NULL;
- }
+ struct lbx_image_priv *img = (struct lbx_image_priv *)pub;
+ unsigned short length, offset;
+ unsigned char buf[4];
- new = malloc(height * sizeof *new);
- if (!new) {
- lbx_error_raise(LBX_ENOMEM);
- free(tmp);
- return NULL;
+ if (img->read_state != READ_STATE_HEADER) {
+ lbx_error_raise(LBX_EINVAL);
+ return -1;
}
- for (i = 0; i < height; i++) {
- new[i] = tmp + i * width;
+ /* Raw images have no row headers */
+ if (img->flags & FLAG_RAW) {
+ img->currentn = img->pub.width;
+ *y = img->currenty++;
+ *x = 0;
+
+ if (*y < img->pub.height) {
+ img->read_state = READ_STATE_DATA;
+ return img->currentn;
+ } else {
+ img->read_state = READ_STATE_DONE;
+ return 0;
+ }
}
- return new;
-}
+ do {
+ if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf) {
+ if (img->fops->eof(img->f))
+ lbx_error_raise(LBX_EEOF);
+ return -1;
+ }
-static unsigned char **read_raw_frame(struct lbx_image_priv *img, int frame)
-{
- unsigned long size = img->pub.width * img->pub.height;
+ length = unpack_16_le(buf+0);
+ offset = unpack_16_le(buf+2);
- assert(img->flags & FLAG_RAW);
+ if (length == 0) {
+ if (offset == 1000) {
+ img->read_state = READ_STATE_DONE;
+ return 0;
+ } else if (offset > img->pub.height - img->currenty) {
+ lbx_error_raise(LBX_EFORMAT);
+ return -1;
+ }
- if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) {
- return NULL;
- }
+ img->currenty += offset;
+ img->currentx = 0;
+ }
+ } while (length == 0);
- if (img->fops->read(img->framedata[0], size, img->f) != size) {
- if (img->fops->eof(img->f))
- lbx_error_raise(LBX_EEOF);
- return NULL;
+ if (offset > img->pub.width - img->currentx) {
+ lbx_error_raise(LBX_EFORMAT);
+ return -1;
}
- memset(img->mask[0], 1, size);
+ img->currentx += offset;
- if (img->fops->tell(img->f) > img->offsets[frame+1]) {
+ if (length > img->pub.width - img->currentx) {
lbx_error_raise(LBX_EFORMAT);
- return NULL;
+ return -1;
}
+ img->currentn = length;
- return img->framedata;
+ img->read_state = READ_STATE_DATA;
+ *x = img->currentx;
+ *y = img->currenty;
+
+ return img->currentn;
}
-unsigned char **lbx_img_getframe(struct lbx_image *pub, int frame)
+long lbx_img_read_row_data(struct lbx_image *pub, void *buf)
{
struct lbx_image_priv *img = (struct lbx_image_priv *)pub;
- unsigned char buf[4];
- if (frame >= pub->frames || frame < 0) {
+ if (img->read_state != READ_STATE_DATA) {
lbx_error_raise(LBX_EINVAL);
- return NULL;
- }
-
- if (!img->framedata) {
- img->framedata = allocframebuffer(pub->width, pub->height);
- if (!img->framedata)
- return NULL;
+ return -1;
}
- if (!img->mask) {
- img->mask = allocframebuffer(pub->width, pub->height);
- if (!img->mask)
- return NULL;
+ if (img->fops->read(buf, img->currentn, img->f) != img->currentn) {
+ if (img->fops->eof(img->f))
+ lbx_error_raise(LBX_EEOF);
+ return -1;
}
- if (img->flags & FLAG_RAW)
- return read_raw_frame(img, frame);
-
- if ((img->flags & FLAG_OVERWRITE)
- || (pub->chunk && !(frame % pub->chunk))) {
- /* Clear the slate. */
- img->currentframe = -1;
- memset(img->framedata[0], 0, pub->width * pub->height);
- memset(img->mask[0], 0, pub->width * pub->height);
- } else {
- /* Start over if we are backtracking. */
- if (img->currentframe > frame) {
- memset(img->mask[0], 0, pub->width * pub->height);
- img->currentframe = -1;
- }
-
- /* We must have previous frame decoded to continue. */
- if (frame > img->currentframe + 1) {
- if (!lbx_img_getframe(pub, frame-1))
- return NULL;
+ if (!(img->flags & FLAG_RAW)) {
+ /* Skip padding byte, if any */
+ if (img->currentn % 2) {
+ if (img->fops->seek(img->f, 1, SEEK_CUR))
+ return -1;
}
}
- if (img->currentframe != frame) {
- int rc;
-
- if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) {
- return NULL;
- }
-
- /* Read frame header */
- if (img->fops->read(buf, 4, img->f) != 4) {
- if (img->fops->eof(img->f))
- lbx_error_raise(LBX_EEOF);
- return NULL;
- }
-
- if (unpack_16_le(buf) != 1) {
- lbx_error_raise(LBX_EFORMAT);
- return NULL;
- }
-
- img->currentx = 0;
- img->currenty = unpack_16_le(buf+2);
- if (img->currenty > img->pub.height) {
- lbx_error_raise(LBX_EFORMAT);
- return NULL;
- }
-
- do {
- rc = _lbx_drawrow(img);
- if (rc == -1)
- return NULL;
+ img->read_state = READ_STATE_HEADER;
+ img->currentx += img->currentn;
- if (img->fops->tell(img->f) > img->offsets[frame+1]) {
- lbx_error_raise(LBX_EFORMAT);
- return NULL;
- }
- } while (!rc);
- }
-
- img->currentframe = frame;
- return img->framedata;
+ return img->currentn;
}
int
}
}
-unsigned char **lbx_img_getmask(struct lbx_image *pub)
-{
- struct lbx_image_priv *img = (struct lbx_image_priv *)pub;
-
- return img->mask;
-}
-
int lbx_img_close(struct lbx_image *pub)
{
struct lbx_image_priv *img = (struct lbx_image_priv *)pub;
int rc = 0;
- if (img) {
- if (img->framedata) {
- free(img->framedata[0]);
- free(img->framedata);
- }
-
- if (img->mask) {
- free(img->mask[0]);
- free(img->mask);
- }
-
- if (img && img->dtor) {
- rc = img->dtor(img->f);
- }
-
- free(img);
+ if (img && img->dtor) {
+ rc = img->dtor(img->f);
}
+ free(img);
return rc;
}