[FFmpeg-cvslog] alac: Convert to the new bitstream reader
Alexandra Hájková
git at videolan.org
Fri May 19 12:00:57 EEST 2017
ffmpeg | branch: master | Alexandra Hájková <alexandra at khirnov.net> | Thu Apr 7 22:04:58 2016 +0200| [4795e4f61f993940c5384044caff56cc15078698] | committer: Diego Biurrun
alac: Convert to the new bitstream reader
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4795e4f61f993940c5384044caff56cc15078698
---
libavcodec/alac.c | 65 ++++++++++++++++++++++++++++---------------------------
1 file changed, 33 insertions(+), 32 deletions(-)
diff --git a/libavcodec/alac.c b/libavcodec/alac.c
index aef68e76a3..0f1c59e486 100644
--- a/libavcodec/alac.c
+++ b/libavcodec/alac.c
@@ -48,19 +48,20 @@
#include <inttypes.h>
#include "libavutil/channel_layout.h"
+
#include "avcodec.h"
-#include "get_bits.h"
+#include "bitstream.h"
#include "bytestream.h"
#include "internal.h"
#include "mathops.h"
-#include "unary_legacy.h"
+#include "unary.h"
#include "alac_data.h"
#define ALAC_EXTRADATA_SIZE 36
typedef struct ALACContext {
AVCodecContext *avctx;
- GetBitContext gb;
+ BitstreamContext bc;
int channels;
int32_t *predict_error_buffer[2];
@@ -77,24 +78,24 @@ typedef struct ALACContext {
int nb_samples; /**< number of samples in the current frame */
} ALACContext;
-static inline unsigned int decode_scalar(GetBitContext *gb, int k, int bps)
+static inline unsigned int decode_scalar(BitstreamContext *bc, int k, int bps)
{
- unsigned int x = get_unary_0_9(gb);
+ unsigned int x = get_unary_0_9(bc);
if (x > 8) { /* RICE THRESHOLD */
/* use alternative encoding */
- x = get_bits_long(gb, bps);
+ x = bitstream_read(bc, bps);
} else if (k != 1) {
- int extrabits = show_bits(gb, k);
+ int extrabits = bitstream_peek(bc, k);
/* multiply x by 2^k - 1, as part of their strange algorithm */
x = (x << k) - x;
if (extrabits > 1) {
x += extrabits - 1;
- skip_bits(gb, k);
+ bitstream_skip(bc, k);
} else
- skip_bits(gb, k - 1);
+ bitstream_skip(bc, k - 1);
}
return x;
}
@@ -113,7 +114,7 @@ static void rice_decompress(ALACContext *alac, int32_t *output_buffer,
/* calculate rice param and decode next value */
k = av_log2((history >> 9) + 3);
k = FFMIN(k, alac->rice_limit);
- x = decode_scalar(&alac->gb, k, bps);
+ x = decode_scalar(&alac->bc, k, bps);
x += sign_modifier;
sign_modifier = 0;
output_buffer[i] = (x >> 1) ^ -(x & 1);
@@ -132,7 +133,7 @@ static void rice_decompress(ALACContext *alac, int32_t *output_buffer,
/* calculate rice param and decode block size */
k = 7 - av_log2(history) + ((history + 16) >> 6);
k = FFMIN(k, alac->rice_limit);
- block_size = decode_scalar(&alac->gb, k, 16);
+ block_size = decode_scalar(&alac->bc, k, 16);
if (block_size > 0) {
if (block_size >= nb_samples - i) {
@@ -257,13 +258,13 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
uint32_t output_samples;
int i, ch;
- skip_bits(&alac->gb, 4); /* element instance tag */
- skip_bits(&alac->gb, 12); /* unused header bits */
+ bitstream_skip(&alac->bc, 4); /* element instance tag */
+ bitstream_skip(&alac->bc, 12); /* unused header bits */
/* the number of output samples is stored in the frame */
- has_size = get_bits1(&alac->gb);
+ has_size = bitstream_read_bit(&alac->bc);
- alac->extra_bits = get_bits(&alac->gb, 2) << 3;
+ alac->extra_bits = bitstream_read(&alac->bc, 2) << 3;
bps = alac->sample_size - alac->extra_bits + channels - 1;
if (bps > 32) {
avpriv_report_missing_feature(avctx, "bps %d", bps);
@@ -271,10 +272,10 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
}
/* whether the frame is compressed */
- is_compressed = !get_bits1(&alac->gb);
+ is_compressed = !bitstream_read_bit(&alac->bc);
if (has_size)
- output_samples = get_bits_long(&alac->gb, 32);
+ output_samples = bitstream_read(&alac->bc, 32);
else
output_samples = alac->max_samples_per_frame;
if (!output_samples || output_samples > alac->max_samples_per_frame) {
@@ -313,27 +314,27 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
return AVERROR(ENOSYS);
}
- decorr_shift = get_bits(&alac->gb, 8);
- decorr_left_weight = get_bits(&alac->gb, 8);
+ decorr_shift = bitstream_read(&alac->bc, 8);
+ decorr_left_weight = bitstream_read(&alac->bc, 8);
for (ch = 0; ch < channels; ch++) {
- prediction_type[ch] = get_bits(&alac->gb, 4);
- lpc_quant[ch] = get_bits(&alac->gb, 4);
- rice_history_mult[ch] = get_bits(&alac->gb, 3);
- lpc_order[ch] = get_bits(&alac->gb, 5);
+ prediction_type[ch] = bitstream_read(&alac->bc, 4);
+ lpc_quant[ch] = bitstream_read(&alac->bc, 4);
+ rice_history_mult[ch] = bitstream_read(&alac->bc, 3);
+ lpc_order[ch] = bitstream_read(&alac->bc, 5);
if (lpc_order[ch] >= alac->max_samples_per_frame)
return AVERROR_INVALIDDATA;
/* read the predictor table */
for (i = lpc_order[ch] - 1; i >= 0; i--)
- lpc_coefs[ch][i] = get_sbits(&alac->gb, 16);
+ lpc_coefs[ch][i] = bitstream_read_signed(&alac->bc, 16);
}
if (alac->extra_bits) {
for (i = 0; i < alac->nb_samples; i++) {
for (ch = 0; ch < channels; ch++)
- alac->extra_bits_buffer[ch][i] = get_bits(&alac->gb, alac->extra_bits);
+ alac->extra_bits_buffer[ch][i] = bitstream_read(&alac->bc, alac->extra_bits);
}
}
for (ch = 0; ch < channels; ch++) {
@@ -366,7 +367,7 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
for (i = 0; i < alac->nb_samples; i++) {
for (ch = 0; ch < channels; ch++) {
alac->output_samples_buffer[ch][i] =
- get_sbits_long(&alac->gb, alac->sample_size);
+ bitstream_read_signed(&alac->bc, alac->sample_size);
}
}
alac->extra_bits = 0;
@@ -412,13 +413,13 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
int channels;
int ch, ret, got_end;
- init_get_bits(&alac->gb, avpkt->data, avpkt->size * 8);
+ bitstream_init8(&alac->bc, avpkt->data, avpkt->size);
got_end = 0;
alac->nb_samples = 0;
ch = 0;
- while (get_bits_left(&alac->gb) >= 3) {
- element = get_bits(&alac->gb, 3);
+ while (bitstream_bits_left(&alac->bc) >= 3) {
+ element = bitstream_read(&alac->bc, 3);
if (element == TYPE_END) {
got_end = 1;
break;
@@ -438,7 +439,7 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
ret = decode_element(avctx, frame,
ff_alac_channel_layout_offsets[alac->channels - 1][ch],
channels);
- if (ret < 0 && get_bits_left(&alac->gb))
+ if (ret < 0 && bitstream_bits_left(&alac->bc))
return ret;
ch += channels;
@@ -452,9 +453,9 @@ static int alac_decode_frame(AVCodecContext *avctx, void *data,
return AVERROR_INVALIDDATA;
}
- if (avpkt->size * 8 - get_bits_count(&alac->gb) > 8) {
+ if (avpkt->size * 8 - bitstream_tell(&alac->bc) > 8) {
av_log(avctx, AV_LOG_ERROR, "Error : %d bits left\n",
- avpkt->size * 8 - get_bits_count(&alac->gb));
+ avpkt->size * 8 - bitstream_tell(&alac->bc));
}
*got_frame_ptr = 1;
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