[FFmpeg-devel] [PATCH v2 1/2] avcodec/dca: convert to AVCRC
foo86
foobaz86 at gmail.com
Tue May 3 02:42:36 CEST 2016
---
libavcodec/dca_core.c | 25 ++++++++++---------------
libavcodec/dca_exss.c | 3 +--
libavcodec/dca_xll.c | 9 +++------
libavcodec/dcadec.c | 29 ++---------------------------
libavcodec/dcadec.h | 19 +++++++++++++++++--
5 files changed, 33 insertions(+), 52 deletions(-)
diff --git a/libavcodec/dca_core.c b/libavcodec/dca_core.c
index 58c78f7..f6c22ca 100644
--- a/libavcodec/dca_core.c
+++ b/libavcodec/dca_core.c
@@ -269,8 +269,7 @@ static int parse_coding_header(DCACoreDecoder *s, enum HeaderType header, int xc
// Check CRC
if (s->xxch_crc_present
- && (s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos, header_pos + header_size * 8)) {
+ && ff_dca_check_crc(s->avctx, &s->gb, header_pos, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid XXCH channel set header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -977,8 +976,7 @@ static int parse_xxch_frame(DCACoreDecoder *s)
header_size = get_bits(&s->gb, 6) + 1;
// Check XXCH frame header CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos + 32, header_pos + header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, header_pos + 32, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid XXCH frame header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -1193,8 +1191,7 @@ static int parse_xbr_frame(DCACoreDecoder *s)
header_size = get_bits(&s->gb, 6) + 1;
// Check XBR frame header CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos + 32, header_pos + header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, header_pos + 32, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid XBR frame header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -1509,8 +1506,7 @@ static int parse_x96_coding_header(DCACoreDecoder *s, int exss, int xch_base)
// Check CRC
if (s->x96_crc_present
- && (s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos, header_pos + header_size * 8)) {
+ && ff_dca_check_crc(s->avctx, &s->gb, header_pos, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid X96 channel set header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -1665,8 +1661,7 @@ static int parse_x96_frame_exss(DCACoreDecoder *s)
header_size = get_bits(&s->gb, 6) + 1;
// Check X96 frame header CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos + 32, header_pos + header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, header_pos + 32, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid X96 frame header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -1785,8 +1780,7 @@ static int parse_aux_data(DCACoreDecoder *s)
skip_bits(&s->gb, 16);
// Check CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, aux_pos, get_bits_count(&s->gb))) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, aux_pos, get_bits_count(&s->gb))) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid auxiliary data checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -1884,9 +1878,10 @@ static int parse_optional_info(DCACoreDecoder *s)
if (AV_RB32(s->gb.buffer + sync_pos * 4) == DCA_SYNCWORD_XXCH) {
s->gb.index = (sync_pos + 1) * 32;
size = get_bits(&s->gb, 6) + 1;
- if (size >= 11 &&
- !ff_dca_check_crc(&s->gb, (sync_pos + 1) * 32,
- sync_pos * 32 + size * 8)) {
+ dist = s->gb.size_in_bits / 8 - sync_pos * 4;
+ if (size >= 11 && size <= dist &&
+ !av_crc(dca->crctab, 0xffff, s->gb.buffer +
+ (sync_pos + 1) * 4, size - 4)) {
s->xxch_pos = sync_pos * 32;
break;
}
diff --git a/libavcodec/dca_exss.c b/libavcodec/dca_exss.c
index 36314c2..87b2f42 100644
--- a/libavcodec/dca_exss.c
+++ b/libavcodec/dca_exss.c
@@ -398,8 +398,7 @@ int ff_dca_exss_parse(DCAExssParser *s, uint8_t *data, int size)
header_size = get_bits(&s->gb, 8 + 4 * wide_hdr) + 1;
// Check CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, 32 + 8, header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, 32 + 8, header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid EXSS header checksum\n");
return AVERROR_INVALIDDATA;
}
diff --git a/libavcodec/dca_xll.c b/libavcodec/dca_xll.c
index 5e6cf35..316af27 100644
--- a/libavcodec/dca_xll.c
+++ b/libavcodec/dca_xll.c
@@ -123,8 +123,7 @@ static int chs_parse_header(DCAXllDecoder *s, DCAXllChSet *c, DCAExssAsset *asse
header_size = get_bits(&s->gb, 10) + 1;
// Check CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, header_pos, header_pos + header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, header_pos, header_pos + header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL sub-header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -784,8 +783,7 @@ static int parse_common_header(DCAXllDecoder *s)
header_size = get_bits(&s->gb, 8) + 1;
// Check CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, 32, header_size * 8)) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, 32, header_size * 8)) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid XLL common header checksum\n");
return AVERROR_INVALIDDATA;
}
@@ -993,8 +991,7 @@ static int parse_navi_table(DCAXllDecoder *s)
skip_bits(&s->gb, 16);
// Check CRC
- if ((s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL))
- && ff_dca_check_crc(&s->gb, navi_pos, get_bits_count(&s->gb))) {
+ if (ff_dca_check_crc(s->avctx, &s->gb, navi_pos, get_bits_count(&s->gb))) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid NAVI checksum\n");
return AVERROR_INVALIDDATA;
}
diff --git a/libavcodec/dcadec.c b/libavcodec/dcadec.c
index 92c2334..f5ddc21 100644
--- a/libavcodec/dcadec.c
+++ b/libavcodec/dcadec.c
@@ -76,33 +76,6 @@ int ff_dca_set_channel_layout(AVCodecContext *avctx, int *ch_remap, int dca_mask
return nchannels;
}
-static uint16_t crc16(const uint8_t *data, int size)
-{
- static const uint16_t crctab[16] = {
- 0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
- 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
- };
-
- uint16_t res = 0xffff;
- int i;
-
- for (i = 0; i < size; i++) {
- res = (res << 4) ^ crctab[(data[i] >> 4) ^ (res >> 12)];
- res = (res << 4) ^ crctab[(data[i] & 15) ^ (res >> 12)];
- }
-
- return res;
-}
-
-int ff_dca_check_crc(GetBitContext *s, int p1, int p2)
-{
- if (((p1 | p2) & 7) || p1 < 0 || p2 > s->size_in_bits || p2 - p1 < 16)
- return -1;
- if (crc16(s->buffer + p1 / 8, (p2 - p1) / 8))
- return -1;
- return 0;
-}
-
void ff_dca_downmix_to_stereo_fixed(DCADSPContext *dcadsp, int32_t **samples,
int *coeff_l, int nsamples, int ch_mask)
{
@@ -359,6 +332,8 @@ static av_cold int dcadec_init(AVCodecContext *avctx)
s->core.dcadsp = &s->dcadsp;
s->xll.dcadsp = &s->dcadsp;
+ s->crctab = av_crc_get_table(AV_CRC_16_CCITT);
+
switch (avctx->request_channel_layout & ~AV_CH_LAYOUT_NATIVE) {
case 0:
s->request_channel_layout = 0;
diff --git a/libavcodec/dcadec.h b/libavcodec/dcadec.h
index 6726121..0d8a145 100644
--- a/libavcodec/dcadec.h
+++ b/libavcodec/dcadec.h
@@ -22,6 +22,7 @@
#define AVCODEC_DCADEC_H
#include "libavutil/common.h"
+#include "libavutil/crc.h"
#include "libavutil/float_dsp.h"
#include "avcodec.h"
@@ -49,6 +50,8 @@ typedef struct DCAContext {
DCADSPContext dcadsp;
+ const AVCRC *crctab;
+
uint8_t *buffer; ///< Packet buffer
unsigned int buffer_size;
@@ -62,13 +65,25 @@ typedef struct DCAContext {
int ff_dca_set_channel_layout(AVCodecContext *avctx, int *ch_remap, int dca_mask);
-int ff_dca_check_crc(GetBitContext *s, int p1, int p2);
-
void ff_dca_downmix_to_stereo_fixed(DCADSPContext *dcadsp, int32_t **samples,
int *coeff_l, int nsamples, int ch_mask);
void ff_dca_downmix_to_stereo_float(AVFloatDSPContext *fdsp, float **samples,
int *coeff_l, int nsamples, int ch_mask);
+static inline int ff_dca_check_crc(AVCodecContext *avctx, GetBitContext *s,
+ int p1, int p2)
+{
+ DCAContext *dca = avctx->priv_data;
+
+ if (!(avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL)))
+ return 0;
+ if (((p1 | p2) & 7) || p1 < 0 || p2 > s->size_in_bits || p2 - p1 < 16)
+ return -1;
+ if (av_crc(dca->crctab, 0xffff, s->buffer + p1 / 8, (p2 - p1) / 8))
+ return -1;
+ return 0;
+}
+
static inline int ff_dca_seek_bits(GetBitContext *s, int p)
{
if (p < s->index || p > s->size_in_bits)
--
2.8.1
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