typedef struct PNGDecContext {
PNGDSPContext dsp;
- const uint8_t *bytestream;
- const uint8_t *bytestream_start;
- const uint8_t *bytestream_end;
+ GetByteContext gb;
AVFrame picture1, picture2;
AVFrame *current_picture, *last_picture;
z_stream zstream;
} PNGDecContext;
+/* Mask to determine which pixels are valid in a pass */
+static const uint8_t png_pass_mask[NB_PASSES] = {
+ 0x01, 0x01, 0x11, 0x11, 0x55, 0x55, 0xff,
+};
+
/* Mask to determine which y pixels can be written in a pass */
static const uint8_t png_pass_dsp_ymask[NB_PASSES] = {
0xff, 0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
uint8_t *d;
const uint8_t *s;
- mask = ff_png_pass_mask[pass];
+ mask = png_pass_mask[pass];
dsp_mask = png_pass_dsp_mask[pass];
switch(bits_per_pixel) {
case 1:
static int png_decode_idat(PNGDecContext *s, int length)
{
int ret;
- s->zstream.avail_in = length;
- s->zstream.next_in = s->bytestream;
- s->bytestream += length;
-
- if(s->bytestream > s->bytestream_end)
- return -1;
+ s->zstream.avail_in = FFMIN(length, bytestream2_get_bytes_left(&s->gb));
+ s->zstream.next_in = (unsigned char *)s->gb.buffer;
+ bytestream2_skip(&s->gb, length);
/* decode one line if possible */
while (s->zstream.avail_in > 0) {
avctx->coded_frame= s->current_picture;
p = s->current_picture;
- s->bytestream_start=
- s->bytestream= buf;
- s->bytestream_end= buf + buf_size;
-
/* check signature */
- if (memcmp(s->bytestream, ff_pngsig, 8) != 0 &&
- memcmp(s->bytestream, ff_mngsig, 8) != 0) {
+ if (buf_size < 8 ||
+ memcmp(buf, ff_pngsig, 8) != 0 &&
+ memcmp(buf, ff_mngsig, 8) != 0) {
av_log(avctx, AV_LOG_ERROR, "Missing png signature\n");
return -1;
}
- s->bytestream+= 8;
+
+ bytestream2_init(&s->gb, buf + 8, buf_size - 8);
s->y=
s->state=0;
// memset(s, 0, sizeof(PNGDecContext));
if (ret != Z_OK)
return -1;
for(;;) {
- int tag32;
- if (s->bytestream >= s->bytestream_end)
+ if (bytestream2_get_bytes_left(&s->gb) <= 0) {
+ av_log(avctx, AV_LOG_ERROR, "No bytes left\n");
goto fail;
- length = bytestream_get_be32(&s->bytestream);
- if (length > 0x7fffffff || length > s->bytestream_end - s->bytestream)
+ }
+
+ length = bytestream2_get_be32(&s->gb);
+ if (length > 0x7fffffff || length > bytestream2_get_bytes_left(&s->gb)) {
+ av_log(avctx, AV_LOG_ERROR, "chunk too big\n");
goto fail;
- tag32 = bytestream_get_be32(&s->bytestream);
- tag = av_bswap32(tag32);
+ }
+ tag = bytestream2_get_le32(&s->gb);
if (avctx->debug & FF_DEBUG_STARTCODE)
av_log(avctx, AV_LOG_DEBUG, "png: tag=%c%c%c%c length=%u\n",
(tag & 0xff),
case MKTAG('I', 'H', 'D', 'R'):
if (length != 13)
goto fail;
- s->width = bytestream_get_be32(&s->bytestream);
- s->height = bytestream_get_be32(&s->bytestream);
+ s->width = bytestream2_get_be32(&s->gb);
+ s->height = bytestream2_get_be32(&s->gb);
if(av_image_check_size(s->width, s->height, 0, avctx)){
s->width= s->height= 0;
+ av_log(avctx, AV_LOG_ERROR, "Invalid image size\n");
goto fail;
}
- s->bit_depth = *s->bytestream++;
- s->color_type = *s->bytestream++;
- s->compression_type = *s->bytestream++;
- s->filter_type = *s->bytestream++;
- s->interlace_type = *s->bytestream++;
- s->bytestream += 4; /* crc */
+ s->bit_depth = bytestream2_get_byte(&s->gb);
+ s->color_type = bytestream2_get_byte(&s->gb);
+ s->compression_type = bytestream2_get_byte(&s->gb);
+ s->filter_type = bytestream2_get_byte(&s->gb);
+ s->interlace_type = bytestream2_get_byte(&s->gb);
+ bytestream2_skip(&s->gb, 4); /* crc */
s->state |= PNG_IHDR;
if (avctx->debug & FF_DEBUG_PICT_INFO)
av_log(avctx, AV_LOG_DEBUG, "width=%d height=%d depth=%d color_type=%d compression_type=%d filter_type=%d interlace_type=%d\n",
s->compression_type, s->filter_type, s->interlace_type);
break;
case MKTAG('I', 'D', 'A', 'T'):
- if (!(s->state & PNG_IHDR))
+ if (!(s->state & PNG_IHDR)) {
+ av_log(avctx, AV_LOG_ERROR, "IDAT without IHDR\n");
goto fail;
+ }
if (!(s->state & PNG_IDAT)) {
/* init image info */
avctx->width = s->width;
} else if (s->bit_depth == 16 &&
s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
avctx->pix_fmt = PIX_FMT_RGBA64BE;
- } else if (s->color_type == PNG_COLOR_TYPE_PALETTE) {
+ } else if ((s->bits_per_pixel == 1 || s->bits_per_pixel == 2 || s->bits_per_pixel == 4 || s->bits_per_pixel == 8) &&
+ s->color_type == PNG_COLOR_TYPE_PALETTE) {
avctx->pix_fmt = PIX_FMT_PAL8;
} else if (s->bit_depth == 1) {
avctx->pix_fmt = PIX_FMT_MONOBLACK;
} else if (s->bit_depth == 8 &&
s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
- avctx->pix_fmt = PIX_FMT_GRAY8A;
+ avctx->pix_fmt = PIX_FMT_Y400A;
} else {
av_log(avctx, AV_LOG_ERROR, "unsupported bit depth %d "
"and color type %d\n",
s->state |= PNG_IDAT;
if (png_decode_idat(s, length) < 0)
goto fail;
- s->bytestream += 4; /* crc */
+ bytestream2_skip(&s->gb, 4); /* crc */
break;
case MKTAG('P', 'L', 'T', 'E'):
{
/* read the palette */
n = length / 3;
for(i=0;i<n;i++) {
- r = *s->bytestream++;
- g = *s->bytestream++;
- b = *s->bytestream++;
+ r = bytestream2_get_byte(&s->gb);
+ g = bytestream2_get_byte(&s->gb);
+ b = bytestream2_get_byte(&s->gb);
s->palette[i] = (0xff << 24) | (r << 16) | (g << 8) | b;
}
for(;i<256;i++) {
s->palette[i] = (0xff << 24);
}
s->state |= PNG_PLTE;
- s->bytestream += 4; /* crc */
+ bytestream2_skip(&s->gb, 4); /* crc */
}
break;
case MKTAG('t', 'R', 'N', 'S'):
!(s->state & PNG_PLTE))
goto skip_tag;
for(i=0;i<length;i++) {
- v = *s->bytestream++;
+ v = bytestream2_get_byte(&s->gb);
s->palette[i] = (s->palette[i] & 0x00ffffff) | (v << 24);
}
- s->bytestream += 4; /* crc */
+ bytestream2_skip(&s->gb, 4); /* crc */
}
break;
case MKTAG('I', 'E', 'N', 'D'):
if (!(s->state & PNG_ALLIMAGE))
+ av_log(avctx, AV_LOG_ERROR, "IEND without all image\n");
+ if (!(s->state & (PNG_ALLIMAGE|PNG_IDAT))) {
goto fail;
- s->bytestream += 4; /* crc */
+ }
+ bytestream2_skip(&s->gb, 4); /* crc */
goto exit_loop;
default:
/* skip tag */
skip_tag:
- s->bytestream += length + 4;
+ bytestream2_skip(&s->gb, length + 4);
break;
}
}
/* handle p-frames only if a predecessor frame is available */
if(s->last_picture->data[0] != NULL) {
- if(!(avpkt->flags & AV_PKT_FLAG_KEY)) {
+ if( !(avpkt->flags & AV_PKT_FLAG_KEY)
+ && s->last_picture->width == s->current_picture->width
+ && s->last_picture->height== s->current_picture->height
+ ) {
int i, j;
uint8_t *pd = s->current_picture->data[0];
uint8_t *pd_last = s->last_picture->data[0];
*picture= *s->current_picture;
*data_size = sizeof(AVFrame);
- ret = s->bytestream - s->bytestream_start;
+ ret = bytestream2_tell(&s->gb);
the_end:
inflateEnd(&s->zstream);
av_free(crow_buf_base);
.close = png_dec_end,
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
- .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
+ .long_name = NULL_IF_CONFIG_SMALL("PNG (Portable Network Graphics) image"),
};
projects / ffmpeg / blobdiff