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Code Issues Releases Activity

avcodec/adpcm: Mono ADPCM for EA WVE Files

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Reviewed-by: Peter Ross <pross@xvid.org>
This commit is contained in:
aaron 2024-07-21 11:18:02 +10:00 committed by Peter Ross
parent 0e32192548
commit f44353cfb6
1 changed files with 32 additions and 12 deletions
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44
libavcodec/adpcm.c
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@ -262,7 +262,7 @@ static av_cold int adpcm_decode_init(AVCodecContext * avctx)
break;
case AV_CODEC_ID_ADPCM_DTK:
case AV_CODEC_ID_ADPCM_EA:
min_channels = 2;
min_channels = 1;
break;
case AV_CODEC_ID_ADPCM_AFC:
case AV_CODEC_ID_ADPCM_EA_R1:
@ -914,10 +914,12 @@ static int get_nb_samples(AVCodecContext *avctx, GetByteContext *gb,
bytestream2_seek(gb, -8, SEEK_CUR);
break;
case AV_CODEC_ID_ADPCM_EA:
/* Stereo is 30 bytes per block */
/* Mono is 15 bytes per block */
has_coded_samples = 1;
*coded_samples = bytestream2_get_le32(gb);
*coded_samples -= *coded_samples % 28;
nb_samples = (buf_size - 12) / 30 * 28;
nb_samples = (buf_size - 12) / (ch == 2 ? 30 : 15) * 28;
break;
case AV_CODEC_ID_ADPCM_IMA_EA_EACS:
has_coded_samples = 1;
@ -1652,10 +1654,10 @@ static int adpcm_decode_frame(AVCodecContext *avctx, AVFrame *frame,
int coeff1l, coeff2l, coeff1r, coeff2r;
int shift_left, shift_right;
/* Each EA ADPCM frame has a 12-byte header followed by 30-byte pieces,
each coding 28 stereo samples. */
/* Each EA ADPCM frame has a 12-byte header followed by 30-byte (stereo) or 15-byte (mono) pieces,
each coding 28 stereo/mono samples. */
if (channels != 2)
if (channels != 2 && channels != 1)
return AVERROR_INVALIDDATA;
current_left_sample = sign_extend(bytestream2_get_le16u(&gb), 16);
@ -1670,11 +1672,16 @@ static int adpcm_decode_frame(AVCodecContext *avctx, AVFrame *frame,
coeff1r = ea_adpcm_table[ byte & 0x0F];
coeff2r = ea_adpcm_table[(byte & 0x0F) + 4];
byte = bytestream2_get_byteu(&gb);
shift_left = 20 - (byte >> 4);
shift_right = 20 - (byte & 0x0F);
if (channels == 2){
byte = bytestream2_get_byteu(&gb);
shift_left = 20 - (byte >> 4);
shift_right = 20 - (byte & 0x0F);
} else{
/* Mono packs the shift into the coefficient byte's lower nibble instead */
shift_left = 20 - (byte & 0x0F);
}
for (int count2 = 0; count2 < 28; count2++) {
for (int count2 = 0; count2 < (channels == 2 ? 28 : 14); count2++) {
byte = bytestream2_get_byteu(&gb);
next_left_sample = sign_extend(byte >> 4, 4) * (1 << shift_left);
next_right_sample = sign_extend(byte, 4) * (1 << shift_right);
@ -1691,11 +1698,24 @@ static int adpcm_decode_frame(AVCodecContext *avctx, AVFrame *frame,
previous_right_sample = current_right_sample;
current_right_sample = av_clip_int16(next_right_sample);
*samples++ = current_left_sample;
*samples++ = current_right_sample;
if (channels == 2){
*samples++ = current_right_sample;
} else {
next_left_sample = sign_extend(byte, 4) * (1 << shift_left);
next_left_sample = (next_left_sample +
(current_left_sample * coeff1l) +
(previous_left_sample * coeff2l) + 0x80) >> 8;
previous_left_sample = current_left_sample;
current_left_sample = av_clip_int16(next_left_sample);
*samples++ = current_left_sample;
}
}
}
bytestream2_skip(&gb, 2); // Skip terminating 0x0000
bytestream2_skip(&gb, channels == 2 ? 2 : 3); // Skip terminating NULs
) /* End of CASE */
CASE(ADPCM_EA_MAXIS_XA,
int coeff[2][2], shift[2];