[FFmpeg-cvslog] exr: zip decompression
Paul B Mahol
git at videolan.org
Wed Jul 11 23:00:34 CEST 2012
ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Sun Jul 8 00:04:46 2012 +0000| [74f3c53b575cf275d87c0a0d3c74d79889a4493d] | committer: Paul B Mahol
exr: zip decompression
Signed-off-by: Paul B Mahol <onemda at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=74f3c53b575cf275d87c0a0d3c74d79889a4493d
---
configure | 1 +
libavcodec/exr.c | 186 +++++++++++++++++++++++++++++++++++++++++++-----------
2 files changed, 149 insertions(+), 38 deletions(-)
diff --git a/configure b/configure
index 1958fa6..8411836 100755
--- a/configure
+++ b/configure
@@ -1467,6 +1467,7 @@ eac3_encoder_select="mdct ac3dsp"
eamad_decoder_select="aandct"
eatgq_decoder_select="aandct"
eatqi_decoder_select="aandct"
+exr_decoder_select="zlib"
ffv1_decoder_select="golomb"
flac_decoder_select="golomb"
flac_encoder_select="golomb lpc"
diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 2628a8c..184687e 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -30,6 +30,8 @@
* exr_flt2uint() and exr_halflt2uint() is credited to Reimar Döffinger
*/
+#include <zlib.h>
+
#include "avcodec.h"
#include "bytestream.h"
#include "libavutil/imgutils.h"
@@ -40,7 +42,8 @@ enum ExrCompr {
EXR_ZIP1 = 2,
EXR_ZIP16 = 3,
EXR_PIZ = 4,
- EXR_B44 = 6
+ EXR_B44 = 6,
+ EXR_B44A = 7,
};
typedef struct EXRContext {
@@ -48,6 +51,12 @@ typedef struct EXRContext {
int compr;
int bits_per_color_id;
int8_t channel_offsets[4]; // 0 = red, 1 = green, 2 = blue and 3 = alpha
+
+ uint8_t *uncompressed_data;
+ int uncompressed_size;
+
+ uint8_t *tmp;
+ int tmp_size;;
} EXRContext;
/**
@@ -142,6 +151,38 @@ static int check_header_variable(AVCodecContext *avctx,
return -1;
}
+static void predictor(uint8_t *src, int size)
+{
+ uint8_t *t = src + 1;
+ uint8_t *stop = src + size;
+
+ while (t < stop) {
+ int d = (int)t[-1] + (int)t[0] - 128;
+ t[0] = d;
+ ++t;
+ }
+}
+
+static void reorder_pixels(uint8_t *src, uint8_t *dst, int size)
+{
+ const int8_t *t1 = src;
+ const int8_t *t2 = src + (size + 1) / 2;
+ int8_t *s = dst;
+ int8_t *stop = s + size;
+
+ while (1) {
+ if (s < stop)
+ *(s++) = *(t1++);
+ else
+ break;
+
+ if (s < stop)
+ *(s++) = *(t2++);
+ else
+ break;
+ }
+}
+
static int decode_frame(AVCodecContext *avctx,
void *data,
int *data_size,
@@ -165,6 +206,10 @@ static int decode_frame(AVCodecContext *avctx,
unsigned int ymax = ~0;
unsigned int xdelta = ~0;
+ int scan_lines_per_block;
+ unsigned long scan_line_size;
+ unsigned long uncompressed_size;
+
unsigned int current_channel_offset = 0;
s->channel_offsets[0] = -1;
@@ -319,10 +364,10 @@ static int decode_frame(AVCodecContext *avctx,
s->compr = *buf;
switch (s->compr) {
case EXR_RAW:
- break;
- case EXR_RLE:
case EXR_ZIP1:
case EXR_ZIP16:
+ break;
+ case EXR_RLE:
case EXR_PIZ:
case EXR_B44:
default:
@@ -382,6 +427,16 @@ static int decode_frame(AVCodecContext *avctx,
return AVERROR_INVALIDDATA;
}
+ switch (s->compr) {
+ case EXR_RAW:
+ case EXR_ZIP1:
+ scan_lines_per_block = 1;
+ break;
+ case EXR_ZIP16:
+ scan_lines_per_block = 16;
+ break;
+ }
+
if (s->picture.data[0])
avctx->release_buffer(avctx, &s->picture);
if (av_image_check_size(w, h, 0, avctx))
@@ -397,6 +452,16 @@ static int decode_frame(AVCodecContext *avctx,
avcodec_set_dimensions(avctx, w, h);
}
+ scan_line_size = xdelta * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components * FFMAX(2 * s->bits_per_color_id, 1);
+ uncompressed_size = scan_line_size * scan_lines_per_block;
+
+ if (s->compr != EXR_RAW) {
+ av_fast_padded_malloc(&s->uncompressed_data, &s->uncompressed_size, uncompressed_size);
+ av_fast_padded_malloc(&s->tmp, &s->tmp_size, uncompressed_size);
+ if (!s->uncompressed_data || !s->tmp)
+ return AVERROR(ENOMEM);
+ }
+
if ((ret = avctx->get_buffer(avctx, p)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
@@ -411,55 +476,94 @@ static int decode_frame(AVCodecContext *avctx,
ptr += stride;
}
- // Process the actual lines
- for (y = ymin; y <= ymax; y++) {
+ // Process the actual scan line blocks
+ for (y = ymin; y <= ymax; y += scan_lines_per_block) {
uint16_t *ptr_x = (uint16_t *)ptr;
if (buf_end - buf > 8) {
/* Read the lineoffset from the line offset table and add 8 bytes
to skip the coordinates and data size fields */
const uint64_t line_offset = bytestream_get_le64(&buf) + 8;
+ int32_t data_size;
+
// Check if the buffer has the required bytes needed from the offset
- if (line_offset > avpkt->size - xdelta * current_channel_offset) {
+ if ((line_offset > buf_size) ||
+ (s->compr == EXR_RAW && line_offset > avpkt->size - xdelta * current_channel_offset) ||
+ (s->compr != EXR_RAW && line_offset > buf_size - (data_size = AV_RL32(avpkt->data + line_offset - 4)))) {
// Line offset is probably wrong and not inside the buffer
av_log(avctx, AV_LOG_WARNING, "Line offset for line %d is out of reach setting it to black\n", y);
- memset(ptr_x, 0, avctx->width * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
+ for (i = 0; i < scan_lines_per_block && y + i <= ymax; i++, ptr += stride) {
+ ptr_x = (uint16_t *)ptr;
+ memset(ptr_x, 0, avctx->width * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
+ }
} else {
- const uint8_t *red_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[0];
- const uint8_t *green_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[1];
- const uint8_t *blue_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[2];
- const uint8_t *alpha_channel_buffer = 0;
-
- if (s->channel_offsets[3] >= 0)
- alpha_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[3];
-
- // Zero out the start if xmin is not 0
- memset(ptr_x, 0, xmin * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
- ptr_x += xmin * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components;
- if (s->bits_per_color_id == 2) {
- // 32-bit
- for (x = 0; x < xdelta; x++) {
- *ptr_x++ = exr_flt2uint(bytestream_get_le32(&red_channel_buffer));
- *ptr_x++ = exr_flt2uint(bytestream_get_le32(&green_channel_buffer));
- *ptr_x++ = exr_flt2uint(bytestream_get_le32(&blue_channel_buffer));
- if (alpha_channel_buffer)
- *ptr_x++ = exr_flt2uint(bytestream_get_le32(&alpha_channel_buffer));
+ const uint8_t *red_channel_buffer, *green_channel_buffer, *blue_channel_buffer, *alpha_channel_buffer = 0;
+
+ if ((s->compr == EXR_ZIP1 || s->compr == EXR_ZIP16) && data_size < uncompressed_size) {
+ if (uncompress(s->tmp, &uncompressed_size, avpkt->data + line_offset, data_size) != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
+ return AVERROR(EINVAL);
}
+
+ predictor(s->tmp, uncompressed_size);
+ reorder_pixels(s->tmp, s->uncompressed_data, uncompressed_size);
+
+ red_channel_buffer = s->uncompressed_data + xdelta * s->channel_offsets[0];
+ green_channel_buffer = s->uncompressed_data + xdelta * s->channel_offsets[1];
+ blue_channel_buffer = s->uncompressed_data + xdelta * s->channel_offsets[2];
+ if (s->channel_offsets[3] >= 0)
+ alpha_channel_buffer = s->uncompressed_data + xdelta * s->channel_offsets[3];
} else {
- // 16-bit
- for (x = 0; x < xdelta; x++) {
- *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&red_channel_buffer));
- *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&green_channel_buffer));
- *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&blue_channel_buffer));
- if (alpha_channel_buffer)
- *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&alpha_channel_buffer));
- }
+ red_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[0];
+ green_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[1];
+ blue_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[2];
+ if (s->channel_offsets[3] >= 0)
+ alpha_channel_buffer = avpkt->data + line_offset + xdelta * s->channel_offsets[3];
}
- // Zero out the end if xmax+1 is not w
- memset(ptr_x, 0, (avctx->width - (xmax + 1)) * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
+ for (i = 0; i < scan_lines_per_block && y + i <= ymax; i++, ptr += stride) {
+ const uint8_t *r, *g, *b, *a;
+
+ r = red_channel_buffer;
+ g = green_channel_buffer;
+ b = blue_channel_buffer;
+ if (alpha_channel_buffer)
+ a = alpha_channel_buffer;
+
+ ptr_x = (uint16_t *)ptr;
+
+ // Zero out the start if xmin is not 0
+ memset(ptr_x, 0, xmin * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
+ ptr_x += xmin * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components;
+ if (s->bits_per_color_id == 2) {
+ // 32-bit
+ for (x = 0; x < xdelta; x++) {
+ *ptr_x++ = exr_flt2uint(bytestream_get_le32(&r));
+ *ptr_x++ = exr_flt2uint(bytestream_get_le32(&g));
+ *ptr_x++ = exr_flt2uint(bytestream_get_le32(&b));
+ if (alpha_channel_buffer)
+ *ptr_x++ = exr_flt2uint(bytestream_get_le32(&a));
+ }
+ } else {
+ // 16-bit
+ for (x = 0; x < xdelta; x++) {
+ *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&r));
+ *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&g));
+ *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&b));
+ if (alpha_channel_buffer)
+ *ptr_x++ = exr_halflt2uint(bytestream_get_le16(&a));
+ }
+ }
+
+ // Zero out the end if xmax+1 is not w
+ memset(ptr_x, 0, (avctx->width - (xmax + 1)) * 2 * av_pix_fmt_descriptors[avctx->pix_fmt].nb_components);
+
+ red_channel_buffer += scan_line_size;
+ green_channel_buffer += scan_line_size;
+ blue_channel_buffer += scan_line_size;
+ if (alpha_channel_buffer)
+ alpha_channel_buffer += scan_line_size;
+ }
}
- // Move to next line
- ptr += stride;
}
}
@@ -478,17 +582,23 @@ static int decode_frame(AVCodecContext *avctx,
static av_cold int decode_init(AVCodecContext *avctx)
{
EXRContext *s = avctx->priv_data;
+
avcodec_get_frame_defaults(&s->picture);
avctx->coded_frame = &s->picture;
+
return 0;
}
static av_cold int decode_end(AVCodecContext *avctx)
{
EXRContext *s = avctx->priv_data;
+
if (s->picture.data[0])
avctx->release_buffer(avctx, &s->picture);
+ av_freep(&s->uncompressed_data);
+ av_freep(&s->tmp);
+
return 0;
}
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