mpc: Convert to the new bitstream reader

libavcodec/mpc7.c

@@ -28,8 +28,9 @@
 #include "libavutil/channel_layout.h"
 #include "libavutil/internal.h"
 #include "libavutil/lfg.h"
+
 #include "avcodec.h"
-#include "get_bits.h"
+#include "bitstream.h"
 #include "internal.h"
 #include "mpegaudiodsp.h"
 
@@ -53,7 +54,7 @@ static av_cold int mpc7_decode_init(AVCodecContext * avctx)
 {
     int i, j;
     MPCContext *c = avctx->priv_data;
-    GetBitContext gb;
+    BitstreamContext bc;
     LOCAL_ALIGNED_16(uint8_t, buf, [16]);
     static int vlc_initialized = 0;
 
@@ -78,18 +79,18 @@ static av_cold int mpc7_decode_init(AVCodecContext * avctx)
     ff_mpadsp_init(&c->mpadsp);
     c->bdsp.bswap_buf((uint32_t *) buf, (const uint32_t *) avctx->extradata, 4);
     ff_mpc_init();
-    init_get_bits(&gb, buf, 128);
+    bitstream_init(&bc, buf, 128);
 
-    c->IS = get_bits1(&gb);
-    c->MSS = get_bits1(&gb);
-    c->maxbands = get_bits(&gb, 6);
+    c->IS       = bitstream_read_bit(&bc);
+    c->MSS      = bitstream_read_bit(&bc);
+    c->maxbands = bitstream_read(&bc, 6);
     if(c->maxbands >= BANDS){
         av_log(avctx, AV_LOG_ERROR, "Too many bands: %i\n", c->maxbands);
         return -1;
     }
-    skip_bits_long(&gb, 88);
-    c->gapless = get_bits1(&gb);
-    c->lastframelen = get_bits(&gb, 11);
+    bitstream_skip(&bc, 88);
+    c->gapless      = bitstream_read_bit(&bc);
+    c->lastframelen = bitstream_read(&bc, 11);
     av_log(avctx, AV_LOG_DEBUG, "IS: %d, MSS: %d, TG: %d, LFL: %d, bands: %d\n",
             c->IS, c->MSS, c->gapless, c->lastframelen, c->maxbands);
     c->frames_to_skip = 0;
@@ -143,7 +144,7 @@ static av_cold int mpc7_decode_init(AVCodecContext * avctx)
 /**
  * Fill samples for given subband
  */
-static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *dst)
+static inline void idx_to_quant(MPCContext *c, BitstreamContext *bc, int idx, int *dst)
 {
     int i, i1, t;
     switch(idx){
@@ -153,43 +154,43 @@ static inline void idx_to_quant(MPCContext *c, GetBitContext *gb, int idx, int *
         }
         break;
     case 1:
-        i1 = get_bits1(gb);
+        i1 = bitstream_read_bit(bc);
         for(i = 0; i < SAMPLES_PER_BAND/3; i++){
-            t = get_vlc2(gb, quant_vlc[0][i1].table, 9, 2);
+            t = bitstream_read_vlc(bc, quant_vlc[0][i1].table, 9, 2);
             *dst++ = mpc7_idx30[t];
             *dst++ = mpc7_idx31[t];
             *dst++ = mpc7_idx32[t];
         }
         break;
     case 2:
-        i1 = get_bits1(gb);
+        i1 = bitstream_read_bit(bc);
         for(i = 0; i < SAMPLES_PER_BAND/2; i++){
-            t = get_vlc2(gb, quant_vlc[1][i1].table, 9, 2);
+            t = bitstream_read_vlc(bc, quant_vlc[1][i1].table, 9, 2);
             *dst++ = mpc7_idx50[t];
             *dst++ = mpc7_idx51[t];
         }
         break;
     case  3: case  4: case  5: case  6: case  7:
-        i1 = get_bits1(gb);
+        i1 = bitstream_read_bit(bc);
         for(i = 0; i < SAMPLES_PER_BAND; i++)
-            *dst++ = get_vlc2(gb, quant_vlc[idx-1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx-1];
+            *dst++ = bitstream_read_vlc(bc, quant_vlc[idx - 1][i1].table, 9, 2) - mpc7_quant_vlc_off[idx - 1];
         break;
     case  8: case  9: case 10: case 11: case 12:
     case 13: case 14: case 15: case 16: case 17:
         t = (1 << (idx - 2)) - 1;
         for(i = 0; i < SAMPLES_PER_BAND; i++)
-            *dst++ = get_bits(gb, idx - 1) - t;
+            *dst++ = bitstream_read(bc, idx - 1) - t;
         break;
     default: // case 0 and -2..-17
         return;
     }
 }
 
-static int get_scale_idx(GetBitContext *gb, int ref)
+static int get_scale_idx(BitstreamContext *bc, int ref)
 {
-    int t = get_vlc2(gb, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
+    int t = bitstream_read_vlc(bc, dscf_vlc.table, MPC7_DSCF_BITS, 1) - 7;
     if (t == 8)
-        return get_bits(gb, 6);
+        return bitstream_read(bc, 6);
     return av_clip_uintp2(ref + t, 7);
 }
 
@@ -200,7 +201,7 @@ static int mpc7_decode_frame(AVCodecContext * avctx, void *data,
     const uint8_t *buf = avpkt->data;
     int buf_size;
     MPCContext *c = avctx->priv_data;
-    GetBitContext gb;
+    BitstreamContext bc;
     int i, ch;
     int mb = -1;
     Band *bands = c->bands;
@@ -237,45 +238,49 @@ static int mpc7_decode_frame(AVCodecContext * avctx, void *data,
         return AVERROR(ENOMEM);
     c->bdsp.bswap_buf((uint32_t *) c->bits, (const uint32_t *) buf,
                       buf_size >> 2);
-    init_get_bits(&gb, c->bits, buf_size * 8);
-    skip_bits_long(&gb, skip);
+    bitstream_init(&bc, c->bits, buf_size * 8);
+    bitstream_skip(&bc, skip);
 
     /* read subband indexes */
     for(i = 0; i <= c->maxbands; i++){
         for(ch = 0; ch < 2; ch++){
             int t = 4;
-            if(i) t = get_vlc2(&gb, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5;
-            if(t == 4) bands[i].res[ch] = get_bits(&gb, 4);
+            if (i)
+                t = bitstream_read_vlc(&bc, hdr_vlc.table, MPC7_HDR_BITS, 1) - 5;
+            if (t == 4)
+                bands[i].res[ch] = bitstream_read(&bc, 4);
             else bands[i].res[ch] = av_clip(bands[i-1].res[ch] + t, 0, 17);
         }
 
         if(bands[i].res[0] || bands[i].res[1]){
             mb = i;
-            if(c->MSS) bands[i].msf = get_bits1(&gb);
+            if (c->MSS)
+                bands[i].msf = bitstream_read_bit(&bc);
         }
     }
     /* get scale indexes coding method */
     for(i = 0; i <= mb; i++)
         for(ch = 0; ch < 2; ch++)
-            if(bands[i].res[ch]) bands[i].scfi[ch] = get_vlc2(&gb, scfi_vlc.table, MPC7_SCFI_BITS, 1);
+            if (bands[i].res[ch])
+                bands[i].scfi[ch] = bitstream_read_vlc(&bc, scfi_vlc.table, MPC7_SCFI_BITS, 1);
     /* get scale indexes */
     for(i = 0; i <= mb; i++){
         for(ch = 0; ch < 2; ch++){
             if(bands[i].res[ch]){
                 bands[i].scf_idx[ch][2] = c->oldDSCF[ch][i];
-                bands[i].scf_idx[ch][0] = get_scale_idx(&gb, bands[i].scf_idx[ch][2]);
+                bands[i].scf_idx[ch][0] = get_scale_idx(&bc, bands[i].scf_idx[ch][2]);
                 switch(bands[i].scfi[ch]){
                 case 0:
-                    bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]);
-                    bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]);
+                    bands[i].scf_idx[ch][1] = get_scale_idx(&bc, bands[i].scf_idx[ch][0]);
+                    bands[i].scf_idx[ch][2] = get_scale_idx(&bc, bands[i].scf_idx[ch][1]);
                     break;
                 case 1:
-                    bands[i].scf_idx[ch][1] = get_scale_idx(&gb, bands[i].scf_idx[ch][0]);
+                    bands[i].scf_idx[ch][1] = get_scale_idx(&bc, bands[i].scf_idx[ch][0]);
                     bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1];
                     break;
                 case 2:
                     bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
-                    bands[i].scf_idx[ch][2] = get_scale_idx(&gb, bands[i].scf_idx[ch][1]);
+                    bands[i].scf_idx[ch][2] = get_scale_idx(&bc, bands[i].scf_idx[ch][1]);
                     break;
                 case 3:
                     bands[i].scf_idx[ch][2] = bands[i].scf_idx[ch][1] = bands[i].scf_idx[ch][0];
@@ -290,11 +295,11 @@ static int mpc7_decode_frame(AVCodecContext * avctx, void *data,
     off = 0;
     for(i = 0; i < BANDS; i++, off += SAMPLES_PER_BAND)
         for(ch = 0; ch < 2; ch++)
-            idx_to_quant(c, &gb, bands[i].res[ch], c->Q[ch] + off);
+            idx_to_quant(c, &bc, bands[i].res[ch], c->Q[ch] + off);
 
     ff_mpc_dequantize_and_synth(c, mb, (int16_t **)frame->extended_data, 2);
 
-    bits_used = get_bits_count(&gb);
+    bits_used = bitstream_tell(&bc);
     bits_avail = buf_size * 8;
     if (!last_frame && ((bits_avail < bits_used) || (bits_used + 32 <= bits_avail))) {
         av_log(avctx, AV_LOG_ERROR, "Error decoding frame: used %i of %i bits\n", bits_used, bits_avail);

libavcodec/mpc8.c

@@ -27,8 +27,9 @@
 
 #include "libavutil/channel_layout.h"
 #include "libavutil/lfg.h"
+
 #include "avcodec.h"
-#include "get_bits.h"
+#include "bitstream.h"
 #include "internal.h"
 #include "mpegaudiodsp.h"
 
@@ -42,22 +43,22 @@ static VLC q1_vlc, q2_vlc[2], q3_vlc[2], quant_vlc[4][2], q9up_vlc;
 static const int q3_offsets[2] = { MPC8_Q3_OFFSET, MPC8_Q4_OFFSET };
 static const int quant_offsets[6] = { MPC8_Q5_OFFSET, MPC8_Q6_OFFSET, MPC8_Q7_OFFSET, MPC8_Q8_OFFSET };
 
-static inline int mpc8_dec_base(GetBitContext *gb, int k, int n)
+static inline int mpc8_dec_base(BitstreamContext *bc, int k, int n)
 {
     int len = mpc8_cnk_len[k-1][n-1] - 1;
-    int code = len ? get_bits_long(gb, len) : 0;
+    int code = len ? bitstream_read(bc, len) : 0;
 
     if (code >= mpc8_cnk_lost[k-1][n-1])
-        code = ((code << 1) | get_bits1(gb)) - mpc8_cnk_lost[k-1][n-1];
+        code = ((code << 1) | bitstream_read_bit(bc)) - mpc8_cnk_lost[k - 1][n - 1];
 
     return code;
 }
 
-static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
+static inline int mpc8_dec_enum(BitstreamContext *bc, int k, int n)
 {
     int bits = 0;
     const uint32_t * C = mpc8_cnk[k-1];
-    int code = mpc8_dec_base(gb, k, n);
+    int code = mpc8_dec_base(bc, k, n);
 
     do {
         n--;
@@ -72,18 +73,18 @@ static inline int mpc8_dec_enum(GetBitContext *gb, int k, int n)
     return bits;
 }
 
-static inline int mpc8_get_mod_golomb(GetBitContext *gb, int m)
+static inline int mpc8_get_mod_golomb(BitstreamContext *bc, int m)
 {
     if(mpc8_cnk_len[0][m] < 1) return 0;
-    return mpc8_dec_base(gb, 1, m+1);
+    return mpc8_dec_base(bc, 1, m + 1);
 }
 
-static int mpc8_get_mask(GetBitContext *gb, int size, int t)
+static int mpc8_get_mask(BitstreamContext *bc, int size, int t)
 {
     int mask = 0;
 
     if(t && t != size)
-         mask = mpc8_dec_enum(gb, FFMIN(t, size - t), size);
+         mask = mpc8_dec_enum(bc, FFMIN(t, size - t), size);
     if((t << 1) > size) mask = ~mask;
 
     return mask;
@@ -97,7 +98,7 @@ static av_cold int mpc8_decode_init(AVCodecContext * avctx)
 {
     int i;
     MPCContext *c = avctx->priv_data;
-    GetBitContext gb;
+    BitstreamContext bc;
     static int vlc_initialized = 0;
     int channels;
 
@@ -122,17 +123,17 @@ static av_cold int mpc8_decode_init(AVCodecContext * avctx)
 
     ff_mpc_init();
 
-    init_get_bits(&gb, avctx->extradata, 16);
+    bitstream_init(&bc, avctx->extradata, 16);
 
-    skip_bits(&gb, 3);//sample rate
-    c->maxbands = get_bits(&gb, 5) + 1;
-    channels = get_bits(&gb, 4) + 1;
+    bitstream_skip(&bc, 3); // sample rate
+    c->maxbands = bitstream_read(&bc, 5) + 1;
+    channels    = bitstream_read(&bc, 4) + 1;
     if (channels > 2) {
         avpriv_request_sample(avctx, "Multichannel MPC SV8");
         return AVERROR_PATCHWELCOME;
     }
-    c->MSS = get_bits1(&gb);
-    c->frames = 1 << (get_bits(&gb, 3) * 2);
+    c->MSS    = bitstream_read_bit(&bc);
+    c->frames = 1 << (bitstream_read(&bc, 3) * 2);
 
     avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
     avctx->channel_layout = (avctx->channels==2) ? AV_CH_LAYOUT_STEREO : AV_CH_LAYOUT_MONO;
@@ -238,7 +239,7 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     MPCContext *c = avctx->priv_data;
-    GetBitContext gb2, *gb = &gb2;
+    BitstreamContext bc2, *bc = &bc2;
     int i, j, k, ch, cnt, res, t;
     Band *bands = c->bands;
     int off;
@@ -258,13 +259,13 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
         memset(c->Q, 0, sizeof(c->Q));
         c->last_bits_used = 0;
     }
-    init_get_bits(gb, buf, buf_size * 8);
-    skip_bits(gb, c->last_bits_used & 7);
+    bitstream_init(bc, buf, buf_size * 8);
+    bitstream_skip(bc, c->last_bits_used & 7);
 
     if(keyframe)
-        maxband = mpc8_get_mod_golomb(gb, c->maxbands + 1);
+        maxband = mpc8_get_mod_golomb(bc, c->maxbands + 1);
     else{
-        maxband = c->last_max_band + get_vlc2(gb, band_vlc.table, MPC8_BANDS_BITS, 2);
+        maxband = c->last_max_band + bitstream_read_vlc(bc, band_vlc.table, MPC8_BANDS_BITS, 2);
         if(maxband > 32) maxband -= 33;
     }
     if(maxband > c->maxbands + 1)
@@ -276,7 +277,7 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
         last[0] = last[1] = 0;
         for(i = maxband - 1; i >= 0; i--){
             for(ch = 0; ch < 2; ch++){
-                last[ch] = get_vlc2(gb, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
+                last[ch] = bitstream_read_vlc(bc, res_vlc[last[ch] > 2].table, MPC8_RES_BITS, 2) + last[ch];
                 if(last[ch] > 15) last[ch] -= 17;
                 bands[i].res[ch] = last[ch];
             }
@@ -288,8 +289,8 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
             for(i = 0; i < maxband; i++)
                 if(bands[i].res[0] || bands[i].res[1])
                     cnt++;
-            t = mpc8_get_mod_golomb(gb, cnt);
-            mask = mpc8_get_mask(gb, cnt, t);
+            t = mpc8_get_mod_golomb(bc, cnt);
+            mask = mpc8_get_mask(bc, cnt, t);
             for(i = maxband - 1; i >= 0; i--)
                 if(bands[i].res[0] || bands[i].res[1]){
                     bands[i].msf = mask & 1;
@@ -309,7 +310,7 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
         if(bands[i].res[0] || bands[i].res[1]){
             cnt = !!bands[i].res[0] + !!bands[i].res[1] - 1;
             if(cnt >= 0){
-                t = get_vlc2(gb, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
+                t = bitstream_read_vlc(bc, scfi_vlc[cnt].table, scfi_vlc[cnt].bits, 1);
                 if(bands[i].res[0]) bands[i].scfi[0] = t >> (2 * cnt);
                 if(bands[i].res[1]) bands[i].scfi[1] = t & 3;
             }
@@ -321,21 +322,21 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
             if(!bands[i].res[ch]) continue;
 
             if(c->oldDSCF[ch][i]){
-                bands[i].scf_idx[ch][0] = get_bits(gb, 7) - 6;
+                bands[i].scf_idx[ch][0] = bitstream_read(bc, 7) - 6;
                 c->oldDSCF[ch][i] = 0;
             }else{
-                t = get_vlc2(gb, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
+                t = bitstream_read_vlc(bc, dscf_vlc[1].table, MPC8_DSCF1_BITS, 2);
                 if(t == 64)
-                    t += get_bits(gb, 6);
+                    t += bitstream_read(bc, 6);
                 bands[i].scf_idx[ch][0] = ((bands[i].scf_idx[ch][2] + t - 25) & 0x7F) - 6;
             }
             for(j = 0; j < 2; j++){
                 if((bands[i].scfi[ch] << j) & 2)
                     bands[i].scf_idx[ch][j + 1] = bands[i].scf_idx[ch][j];
                 else{
-                    t = get_vlc2(gb, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
+                    t = bitstream_read_vlc(bc, dscf_vlc[0].table, MPC8_DSCF0_BITS, 2);
                     if(t == 31)
-                        t = 64 + get_bits(gb, 6);
+                        t = 64 + bitstream_read(bc, 6);
                     bands[i].scf_idx[ch][j + 1] = ((bands[i].scf_idx[ch][j] + t - 25) & 0x7F) - 6;
                 }
             }
@@ -354,16 +355,16 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
                 break;
             case 1:
                 for(j = 0; j < SAMPLES_PER_BAND; j += SAMPLES_PER_BAND / 2){
-                    cnt = get_vlc2(gb, q1_vlc.table, MPC8_Q1_BITS, 2);
-                    t = mpc8_get_mask(gb, 18, cnt);
+                    cnt = bitstream_read_vlc(bc, q1_vlc.table, MPC8_Q1_BITS, 2);
+                    t = mpc8_get_mask(bc, 18, cnt);
                     for(k = 0; k < SAMPLES_PER_BAND / 2; k++, t <<= 1)
-                        c->Q[ch][off + j + k] = (t & 0x20000) ? (get_bits1(gb) << 1) - 1 : 0;
+                        c->Q[ch][off + j + k] = (t & 0x20000) ? (bitstream_read_bit(bc) << 1) - 1 : 0;
                 }
                 break;
             case 2:
                 cnt = 6;//2*mpc8_thres[res]
                 for(j = 0; j < SAMPLES_PER_BAND; j += 3){
-                    t = get_vlc2(gb, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
+                    t = bitstream_read_vlc(bc, q2_vlc[cnt > 3].table, MPC8_Q2_BITS, 2);
                     c->Q[ch][off + j + 0] = mpc8_idx50[t];
                     c->Q[ch][off + j + 1] = mpc8_idx51[t];
                     c->Q[ch][off + j + 2] = mpc8_idx52[t];
@@ -373,7 +374,7 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
             case 3:
             case 4:
                 for(j = 0; j < SAMPLES_PER_BAND; j += 2){
-                    t = get_vlc2(gb, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
+                    t = bitstream_read_vlc(bc, q3_vlc[res - 3].table, MPC8_Q3_BITS, 2) + q3_offsets[res - 3];
                     c->Q[ch][off + j + 1] = t >> 4;
                     c->Q[ch][off + j + 0] = (t & 8) ? (t & 0xF) - 16 : (t & 0xF);
                 }
@@ -384,17 +385,17 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
             case 8:
                 cnt = 2 * mpc8_thres[res];
                 for(j = 0; j < SAMPLES_PER_BAND; j++){
-                    t = get_vlc2(gb, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
+                    t = bitstream_read_vlc(bc, quant_vlc[res - 5][cnt > mpc8_thres[res]].table, quant_vlc[res - 5][cnt > mpc8_thres[res]].bits, 2) + quant_offsets[res - 5];
                     c->Q[ch][off + j] = t;
                     cnt = (cnt >> 1) + FFABS(c->Q[ch][off + j]);
                 }
                 break;
             default:
                 for(j = 0; j < SAMPLES_PER_BAND; j++){
-                    c->Q[ch][off + j] = get_vlc2(gb, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
+                    c->Q[ch][off + j] = bitstream_read_vlc(bc, q9up_vlc.table, MPC8_Q9UP_BITS, 2);
                     if(res != 9){
                         c->Q[ch][off + j] <<= res - 9;
-                        c->Q[ch][off + j] |= get_bits(gb, res - 9);
+                        c->Q[ch][off + j] |= bitstream_read(bc, res - 9);
                     }
                     c->Q[ch][off + j] -= (1 << (res - 2)) - 1;
                 }
@@ -408,8 +409,8 @@ static int mpc8_decode_frame(AVCodecContext * avctx, void *data,
 
     c->cur_frame++;
 
-    c->last_bits_used = get_bits_count(gb);
-    if(get_bits_left(gb) < 8) // we have only padding left
+    c->last_bits_used = bitstream_tell(bc);
+    if (bitstream_bits_left(bc) < 8) // we have only padding left
         c->last_bits_used = buf_size << 3;
     if(c->cur_frame >= c->frames)
         c->cur_frame = 0;

libavformat/mpc8.c

@@ -19,8 +19,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavcodec/get_bits.h"
-#include "libavcodec/unary_legacy.h"
+#include "libavcodec/bitstream.h"
+#include "libavcodec/unary.h"
 
 #include "apetag.h"
 #include "avformat.h"
@@ -107,17 +107,17 @@ static int mpc8_probe(AVProbeData *p)
     return 0;
 }
 
-static inline int64_t gb_get_v(GetBitContext *gb)
+static inline int64_t gb_get_v(BitstreamContext *bc)
 {
     int64_t v = 0;
     int bits = 0;
-    while(get_bits1(gb) && bits < 64-7){
+    while (bitstream_read_bit(bc) && bits < 64 - 7) {
         v <<= 7;
-        v |= get_bits(gb, 7);
+        v |= bitstream_read(bc, 7);
         bits += 7;
     }
     v <<= 7;
-    v |= get_bits(gb, 7);
+    v |= bitstream_read(bc, 7);
 
     return v;
 }
@@ -138,7 +138,7 @@ static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
     int64_t size, pos, ppos[2];
     uint8_t *buf;
     int i, t, seekd;
-    GetBitContext gb;
+    BitstreamContext bc;
 
     if (s->nb_streams == 0) {
         av_log(s, AV_LOG_ERROR, "No stream added before parsing seek table\n");
@@ -158,21 +158,21 @@ static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
     if(!(buf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE)))
         return;
     avio_read(s->pb, buf, size);
-    init_get_bits(&gb, buf, size * 8);
-    size = gb_get_v(&gb);
+    bitstream_init8(&bc, buf, size);
+    size = gb_get_v(&bc);
     if(size > UINT_MAX/4 || size > c->samples/1152){
         av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
         return;
     }
-    seekd = get_bits(&gb, 4);
+    seekd = bitstream_read(&bc, 4);
     for(i = 0; i < 2; i++){
-        pos = gb_get_v(&gb) + c->header_pos;
+        pos = gb_get_v(&bc) + c->header_pos;
         ppos[1 - i] = pos;
         av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
     }
     for(; i < size; i++){
-        t = get_unary(&gb, 1, 33) << 12;
-        t += get_bits(&gb, 12);
+        t = get_unary(&bc, 1, 33) << 12;
+        t += bitstream_read(&bc, 12);
         if(t & 1)
             t = -(t & ~1);
         pos = (t >> 1) + ppos[0]*2 - ppos[1];