Add MxPEG decoder

[ffmpeg] / libavcodec / ac3dec.c

diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
index e08efa104cb67a3229ce2048c2e72a27846025b6..431f67dc2310579a0055d5f522179964d292bf93 100644 (file)
--- a/libavcodec/ac3dec.c
+++ b/libavcodec/ac3dec.c
@@ -7,20 +7,20 @@
  * Copyright (c) 2007-2008 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
  * Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com>
  *
- * This file is part of Libav.
+ * This file is part of FFmpeg.
  *
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -37,9 +37,6 @@
 #include "ac3dec_data.h"
 #include "kbdwin.h"
 
-/** Large enough for maximum possible frame size when the specification limit is ignored */
-#define AC3_FRAME_BUFFER_SIZE 32768
-
 /**
  * table for ungrouping 3 values in 7 bits.
  * used for exponents and bap=2 mantissas
@@ -184,12 +181,10 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx)
     ff_mdct_init(&s->imdct_512, 9, 1, 1.0);
     ff_kbd_window_init(s->window, 5.0, 256);
     dsputil_init(&s->dsp, avctx);
+    ff_ac3dsp_init(&s->ac3dsp, avctx->flags & CODEC_FLAG_BITEXACT);
     ff_fmt_convert_init(&s->fmt_conv, avctx);
     av_lfg_init(&s->dith_state, 0);
 
-    /* set scale value for float to int16 conversion */
-    s->mul_bias = 32767.0f;
-
     /* allow downmixing to stereo or mono */
     if (avctx->channels > 0 && avctx->request_channels > 0 &&
             avctx->request_channels < avctx->channels &&
@@ -198,12 +193,14 @@ static av_cold int ac3_decode_init(AVCodecContext *avctx)
     }
     s->downmixed = 1;
 
-    /* allocate context input buffer */
-        s->input_buffer = av_mallocz(AC3_FRAME_BUFFER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
-        if (!s->input_buffer)
-            return AVERROR(ENOMEM);
-
-    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+    if (avctx->request_sample_fmt == AV_SAMPLE_FMT_FLT) {
+        avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
+        s->mul_bias = 1.0f;
+    } else {
+        avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+        /* set scale value for float to int16 conversion */
+        s->mul_bias = 32767.0f;
+    }
     return 0;
 }
 
@@ -1172,8 +1169,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
         /* channel delta offset, len and bit allocation */
         for (ch = !cpl_in_use; ch <= fbw_channels; ch++) {
             if (s->dba_mode[ch] == DBA_NEW) {
-                s->dba_nsegs[ch] = get_bits(gbc, 3);
-                for (seg = 0; seg <= s->dba_nsegs[ch]; seg++) {
+                s->dba_nsegs[ch] = get_bits(gbc, 3) + 1;
+                for (seg = 0; seg < s->dba_nsegs[ch]; seg++) {
                     s->dba_offsets[ch][seg] = get_bits(gbc, 5);
                     s->dba_lengths[ch][seg] = get_bits(gbc, 4);
                     s->dba_values[ch][seg] = get_bits(gbc, 3);
@@ -1213,7 +1210,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             /* Compute bit allocation */
             const uint8_t *bap_tab = s->channel_uses_aht[ch] ?
                                      ff_eac3_hebap_tab : ff_ac3_bap_tab;
-            ff_ac3_bit_alloc_calc_bap(s->mask[ch], s->psd[ch],
+            s->ac3dsp.bit_alloc_calc_bap(s->mask[ch], s->psd[ch],
                                       s->start_freq[ch], s->end_freq[ch],
                                       s->snr_offset[ch],
                                       s->bit_alloc_params.floor,
@@ -1298,6 +1295,7 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     AC3DecodeContext *s = avctx->priv_data;
+    float *out_samples_flt = (float *)data;
     int16_t *out_samples = (int16_t *)data;
     int blk, ch, err;
     const uint8_t *channel_map;
@@ -1404,10 +1402,16 @@ static int ac3_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
             av_log(avctx, AV_LOG_ERROR, "error decoding the audio block\n");
             err = 1;
         }
-        s->fmt_conv.float_to_int16_interleave(out_samples, output, 256, s->out_channels);
-        out_samples += 256 * s->out_channels;
+        if (avctx->sample_fmt == AV_SAMPLE_FMT_FLT) {
+            float_interleave_noscale(out_samples_flt, output, 256, s->out_channels);
+            out_samples_flt += 256 * s->out_channels;
+        } else {
+            s->fmt_conv.float_to_int16_interleave(out_samples, output, 256, s->out_channels);
+            out_samples += 256 * s->out_channels;
+        }
     }
-    *data_size = s->num_blocks * 256 * avctx->channels * sizeof (int16_t);
+    *data_size = s->num_blocks * 256 * avctx->channels;
+    *data_size *= avctx->sample_fmt == AV_SAMPLE_FMT_FLT ? sizeof(*out_samples_flt) : sizeof(*out_samples);
     return FFMIN(buf_size, s->frame_size);
 }
 
@@ -1420,8 +1424,6 @@ static av_cold int ac3_decode_end(AVCodecContext *avctx)
     ff_mdct_end(&s->imdct_512);
     ff_mdct_end(&s->imdct_256);
 
-    av_freep(&s->input_buffer);
-
     return 0;
 }