[FFmpeg-devel] [PATCH 03/10] avcodec: add avpriv_dca_parse_core_frame_header()
foo86
foobaz86 at gmail.com
Mon Jul 10 17:11:33 EEST 2017
There are 3 different places where DCA core frame header is parsed:
decoder, parser and demuxer. Each one uses ad-hoc code. Add common core
frame header parsing function that will be used in all places.
---
libavcodec/dca.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/dca.h | 49 ++++++++++++++++++++++++++++++++++++++++++
libavcodec/version.h | 4 ++--
3 files changed, 111 insertions(+), 2 deletions(-)
diff --git a/libavcodec/dca.c b/libavcodec/dca.c
index fb796191d6..39f8f3d81c 100644
--- a/libavcodec/dca.c
+++ b/libavcodec/dca.c
@@ -28,7 +28,9 @@
#include "libavutil/error.h"
#include "dca.h"
+#include "dca_core.h"
#include "dca_syncwords.h"
+#include "get_bits.h"
#include "put_bits.h"
const uint32_t avpriv_dca_sample_rates[16] = {
@@ -85,3 +87,61 @@ int avpriv_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst,
return AVERROR_INVALIDDATA;
}
}
+
+int avpriv_dca_parse_core_frame_header(GetBitContext *gb, DCACoreFrameHeader *h)
+{
+ if (get_bits_long(gb, 32) != DCA_SYNCWORD_CORE_BE)
+ return DCA_PARSE_ERROR_SYNC_WORD;
+
+ h->normal_frame = get_bits1(gb);
+ h->deficit_samples = get_bits(gb, 5) + 1;
+ if (h->deficit_samples != DCA_PCMBLOCK_SAMPLES)
+ return DCA_PARSE_ERROR_DEFICIT_SAMPLES;
+
+ h->crc_present = get_bits1(gb);
+ h->npcmblocks = get_bits(gb, 7) + 1;
+ if (h->npcmblocks & (DCA_SUBBAND_SAMPLES - 1))
+ return DCA_PARSE_ERROR_PCM_BLOCKS;
+
+ h->frame_size = get_bits(gb, 14) + 1;
+ if (h->frame_size < 96)
+ return DCA_PARSE_ERROR_FRAME_SIZE;
+
+ h->audio_mode = get_bits(gb, 6);
+ if (h->audio_mode >= DCA_AMODE_COUNT)
+ return DCA_PARSE_ERROR_AMODE;
+
+ h->sr_code = get_bits(gb, 4);
+ if (!avpriv_dca_sample_rates[h->sr_code])
+ return DCA_PARSE_ERROR_SAMPLE_RATE;
+
+ h->br_code = get_bits(gb, 5);
+ if (get_bits1(gb))
+ return DCA_PARSE_ERROR_RESERVED_BIT;
+
+ h->drc_present = get_bits1(gb);
+ h->ts_present = get_bits1(gb);
+ h->aux_present = get_bits1(gb);
+ h->hdcd_master = get_bits1(gb);
+ h->ext_audio_type = get_bits(gb, 3);
+ h->ext_audio_present = get_bits1(gb);
+ h->sync_ssf = get_bits1(gb);
+ h->lfe_present = get_bits(gb, 2);
+ if (h->lfe_present == DCA_LFE_FLAG_INVALID)
+ return DCA_PARSE_ERROR_LFE_FLAG;
+
+ h->predictor_history = get_bits1(gb);
+ if (h->crc_present)
+ skip_bits(gb, 16);
+ h->filter_perfect = get_bits1(gb);
+ h->encoder_rev = get_bits(gb, 4);
+ h->copy_hist = get_bits(gb, 2);
+ h->pcmr_code = get_bits(gb, 3);
+ if (!ff_dca_bits_per_sample[h->pcmr_code])
+ return DCA_PARSE_ERROR_PCM_RES;
+
+ h->sumdiff_front = get_bits1(gb);
+ h->sumdiff_surround = get_bits1(gb);
+ h->dn_code = get_bits(gb, 4);
+ return 0;
+}
diff --git a/libavcodec/dca.h b/libavcodec/dca.h
index 1d10de4b94..cf6204e554 100644
--- a/libavcodec/dca.h
+++ b/libavcodec/dca.h
@@ -32,6 +32,49 @@
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
+#include "get_bits.h"
+
+#define DCA_CORE_FRAME_HEADER_SIZE 18
+
+enum DCAParseError {
+ DCA_PARSE_ERROR_SYNC_WORD = -1,
+ DCA_PARSE_ERROR_DEFICIT_SAMPLES = -2,
+ DCA_PARSE_ERROR_PCM_BLOCKS = -3,
+ DCA_PARSE_ERROR_FRAME_SIZE = -4,
+ DCA_PARSE_ERROR_AMODE = -5,
+ DCA_PARSE_ERROR_SAMPLE_RATE = -6,
+ DCA_PARSE_ERROR_RESERVED_BIT = -7,
+ DCA_PARSE_ERROR_LFE_FLAG = -8,
+ DCA_PARSE_ERROR_PCM_RES = -9
+};
+
+typedef struct DCACoreFrameHeader {
+ uint8_t normal_frame; ///< Frame type
+ uint8_t deficit_samples; ///< Deficit sample count
+ uint8_t crc_present; ///< CRC present flag
+ uint8_t npcmblocks; ///< Number of PCM sample blocks
+ uint16_t frame_size; ///< Primary frame byte size
+ uint8_t audio_mode; ///< Audio channel arrangement
+ uint8_t sr_code; ///< Core audio sampling frequency
+ uint8_t br_code; ///< Transmission bit rate
+ uint8_t drc_present; ///< Embedded dynamic range flag
+ uint8_t ts_present; ///< Embedded time stamp flag
+ uint8_t aux_present; ///< Auxiliary data flag
+ uint8_t hdcd_master; ///< HDCD mastering flag
+ uint8_t ext_audio_type; ///< Extension audio descriptor flag
+ uint8_t ext_audio_present; ///< Extended coding flag
+ uint8_t sync_ssf; ///< Audio sync word insertion flag
+ uint8_t lfe_present; ///< Low frequency effects flag
+ uint8_t predictor_history; ///< Predictor history flag switch
+ uint8_t filter_perfect; ///< Multirate interpolator switch
+ uint8_t encoder_rev; ///< Encoder software revision
+ uint8_t copy_hist; ///< Copy history
+ uint8_t pcmr_code; ///< Source PCM resolution
+ uint8_t sumdiff_front; ///< Front sum/difference flag
+ uint8_t sumdiff_surround; ///< Surround sum/difference flag
+ uint8_t dn_code; ///< Dialog normalization / unspecified
+} DCACoreFrameHeader;
+
enum DCASpeaker {
DCA_SPEAKER_C, DCA_SPEAKER_L, DCA_SPEAKER_R, DCA_SPEAKER_Ls,
DCA_SPEAKER_Rs, DCA_SPEAKER_LFE1, DCA_SPEAKER_Cs, DCA_SPEAKER_Lsr,
@@ -165,4 +208,10 @@ extern const uint8_t ff_dca_bits_per_sample[8];
int avpriv_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst,
int max_size);
+/**
+ * Parse and validate core frame header
+ * @return 0 on success, negative DCA_PARSE_ERROR_ code on failure
+ */
+int avpriv_dca_parse_core_frame_header(GetBitContext *gb, DCACoreFrameHeader *h);
+
#endif /* AVCODEC_DCA_H */
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 096b062e97..5b99785a72 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -28,8 +28,8 @@
#include "libavutil/version.h"
#define LIBAVCODEC_VERSION_MAJOR 57
-#define LIBAVCODEC_VERSION_MINOR 100
-#define LIBAVCODEC_VERSION_MICRO 104
+#define LIBAVCODEC_VERSION_MINOR 101
+#define LIBAVCODEC_VERSION_MICRO 100
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
LIBAVCODEC_VERSION_MINOR, \
--
2.11.0
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