[FFmpeg-devel] [PATCH 04/10] avcodec/pngdec: create a function to decode IDAT chunk.
Benoit Fouet
benoit.fouet at free.fr
Fri Nov 14 10:17:33 CET 2014
---
libavcodec/pngdec.c | 207 +++++++++++++++++++++++++++-------------------------
1 file changed, 109 insertions(+), 98 deletions(-)
diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 99a3a72..8199bd8 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -563,6 +563,114 @@ static int decode_phys_chunk(AVCodecContext *avctx, PNGDecContext *s)
return 0;
}
+static int decode_idat_chunk(AVCodecContext *avctx, PNGDecContext *s,
+ uint32_t length, AVFrame *p)
+{
+ int ret;
+
+ if (!(s->state & PNG_IHDR)) {
+ av_log(avctx, AV_LOG_ERROR, "IDAT without IHDR\n");
+ return AVERROR_INVALIDDATA;
+ }
+ if (!(s->state & PNG_IDAT)) {
+ /* init image info */
+ avctx->width = s->width;
+ avctx->height = s->height;
+
+ s->channels = ff_png_get_nb_channels(s->color_type);
+ s->bits_per_pixel = s->bit_depth * s->channels;
+ s->bpp = (s->bits_per_pixel + 7) >> 3;
+ s->row_size = (avctx->width * s->bits_per_pixel + 7) >> 3;
+
+ if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
+ s->color_type == PNG_COLOR_TYPE_RGB) {
+ avctx->pix_fmt = AV_PIX_FMT_RGB24;
+ } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
+ s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
+ avctx->pix_fmt = AV_PIX_FMT_RGBA;
+ } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
+ s->color_type == PNG_COLOR_TYPE_GRAY) {
+ avctx->pix_fmt = AV_PIX_FMT_GRAY8;
+ } else if (s->bit_depth == 16 &&
+ s->color_type == PNG_COLOR_TYPE_GRAY) {
+ avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
+ } else if (s->bit_depth == 16 &&
+ s->color_type == PNG_COLOR_TYPE_RGB) {
+ avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
+ } else if (s->bit_depth == 16 &&
+ s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
+ avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
+ } 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 = AV_PIX_FMT_PAL8;
+ } else if (s->bit_depth == 1 && s->bits_per_pixel == 1) {
+ avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
+ } else if (s->bit_depth == 8 &&
+ s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
+ avctx->pix_fmt = AV_PIX_FMT_YA8;
+ } else if (s->bit_depth == 16 &&
+ s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
+ avctx->pix_fmt = AV_PIX_FMT_YA16BE;
+ } else {
+ av_log(avctx, AV_LOG_ERROR, "unsupported bit depth %d "
+ "and color type %d\n",
+ s->bit_depth, s->color_type);
+ return AVERROR_INVALIDDATA;
+ }
+
+ if ((ret = ff_thread_get_buffer(avctx, &s->picture, AV_GET_BUFFER_FLAG_REF)) < 0)
+ return ret;
+ ff_thread_finish_setup(avctx);
+
+ p->pict_type = AV_PICTURE_TYPE_I;
+ p->key_frame = 1;
+ p->interlaced_frame = !!s->interlace_type;
+
+ /* compute the compressed row size */
+ if (!s->interlace_type) {
+ s->crow_size = s->row_size + 1;
+ } else {
+ s->pass = 0;
+ s->pass_row_size = ff_png_pass_row_size(s->pass,
+ s->bits_per_pixel,
+ s->width);
+ s->crow_size = s->pass_row_size + 1;
+ }
+ av_dlog(avctx, "row_size=%d crow_size =%d\n",
+ s->row_size, s->crow_size);
+ s->image_buf = p->data[0];
+ s->image_linesize = p->linesize[0];
+ /* copy the palette if needed */
+ if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
+ memcpy(p->data[1], s->palette, 256 * sizeof(uint32_t));
+ /* empty row is used if differencing to the first row */
+ av_fast_padded_mallocz(&s->last_row, &s->last_row_size, s->row_size);
+ if (!s->last_row)
+ return AVERROR_INVALIDDATA;
+ if (s->interlace_type ||
+ s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
+ av_fast_padded_malloc(&s->tmp_row, &s->tmp_row_size, s->row_size);
+ if (!s->tmp_row)
+ return AVERROR_INVALIDDATA;
+ }
+ /* compressed row */
+ av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
+ if (!s->buffer)
+ return AVERROR(ENOMEM);
+
+ /* we want crow_buf+1 to be 16-byte aligned */
+ s->crow_buf = s->buffer + 15;
+ s->zstream.avail_out = s->crow_size;
+ s->zstream.next_out = s->crow_buf;
+ }
+ s->state |= PNG_IDAT;
+ if ((ret = png_decode_idat(s, length)) < 0)
+ return ret;
+ bytestream2_skip(&s->gb, 4); /* crc */
+
+ return 0;
+}
+
static int decode_frame_png(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
@@ -632,105 +740,8 @@ static int decode_frame_png(AVCodecContext *avctx,
goto fail;
break;
case MKTAG('I', 'D', 'A', 'T'):
- 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;
- avctx->height = s->height;
-
- s->channels = ff_png_get_nb_channels(s->color_type);
- s->bits_per_pixel = s->bit_depth * s->channels;
- s->bpp = (s->bits_per_pixel + 7) >> 3;
- s->row_size = (avctx->width * s->bits_per_pixel + 7) >> 3;
-
- if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
- s->color_type == PNG_COLOR_TYPE_RGB) {
- avctx->pix_fmt = AV_PIX_FMT_RGB24;
- } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
- s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- avctx->pix_fmt = AV_PIX_FMT_RGBA;
- } else if ((s->bit_depth == 2 || s->bit_depth == 4 || s->bit_depth == 8) &&
- s->color_type == PNG_COLOR_TYPE_GRAY) {
- avctx->pix_fmt = AV_PIX_FMT_GRAY8;
- } else if (s->bit_depth == 16 &&
- s->color_type == PNG_COLOR_TYPE_GRAY) {
- avctx->pix_fmt = AV_PIX_FMT_GRAY16BE;
- } else if (s->bit_depth == 16 &&
- s->color_type == PNG_COLOR_TYPE_RGB) {
- avctx->pix_fmt = AV_PIX_FMT_RGB48BE;
- } else if (s->bit_depth == 16 &&
- s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- avctx->pix_fmt = AV_PIX_FMT_RGBA64BE;
- } 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 = AV_PIX_FMT_PAL8;
- } else if (s->bit_depth == 1 && s->bits_per_pixel == 1) {
- avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
- } else if (s->bit_depth == 8 &&
- s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
- avctx->pix_fmt = AV_PIX_FMT_YA8;
- } else if (s->bit_depth == 16 &&
- s->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
- avctx->pix_fmt = AV_PIX_FMT_YA16BE;
- } else {
- av_log(avctx, AV_LOG_ERROR, "unsupported bit depth %d "
- "and color type %d\n",
- s->bit_depth, s->color_type);
- goto fail;
- }
-
- if (ff_thread_get_buffer(avctx, &s->picture, AV_GET_BUFFER_FLAG_REF) < 0)
- goto fail;
- ff_thread_finish_setup(avctx);
-
- p->pict_type = AV_PICTURE_TYPE_I;
- p->key_frame = 1;
- p->interlaced_frame = !!s->interlace_type;
-
- /* compute the compressed row size */
- if (!s->interlace_type) {
- s->crow_size = s->row_size + 1;
- } else {
- s->pass = 0;
- s->pass_row_size = ff_png_pass_row_size(s->pass,
- s->bits_per_pixel,
- s->width);
- s->crow_size = s->pass_row_size + 1;
- }
- av_dlog(avctx, "row_size=%d crow_size =%d\n",
- s->row_size, s->crow_size);
- s->image_buf = p->data[0];
- s->image_linesize = p->linesize[0];
- /* copy the palette if needed */
- if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
- memcpy(p->data[1], s->palette, 256 * sizeof(uint32_t));
- /* empty row is used if differencing to the first row */
- av_fast_padded_mallocz(&s->last_row, &s->last_row_size, s->row_size);
- if (!s->last_row)
- goto fail;
- if (s->interlace_type ||
- s->color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
- av_fast_padded_malloc(&s->tmp_row, &s->tmp_row_size, s->row_size);
- if (!s->tmp_row)
- goto fail;
- }
- /* compressed row */
- av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
- if (!s->buffer)
- goto fail;
-
- /* we want crow_buf+1 to be 16-byte aligned */
- s->crow_buf = s->buffer + 15;
- s->zstream.avail_out = s->crow_size;
- s->zstream.next_out = s->crow_buf;
- }
- s->state |= PNG_IDAT;
- if (png_decode_idat(s, length) < 0)
+ if (decode_idat_chunk(avctx, s, length, p) < 0)
goto fail;
- bytestream2_skip(&s->gb, 4); /* crc */
break;
case MKTAG('P', 'L', 'T', 'E'):
{
--
2.2.0.rc1.23.gf570943
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