diff --git a/libavcodec/loco.c b/libavcodec/loco.c
index b530fd6503864957ba02b632e07a212aefe81bb5..93377e2220631b9ab3f45d1fc51448b757236837 100644
--- a/libavcodec/loco.c
+++ b/libavcodec/loco.c
@@ -30,29 +30,39 @@
 #include "internal.h"
 #include "mathops.h"
 
-enum LOCO_MODE {LOCO_UNKN=0, LOCO_CYUY2=-1, LOCO_CRGB=-2, LOCO_CRGBA=-3, LOCO_CYV12=-4,
- LOCO_YUY2=1, LOCO_UYVY=2, LOCO_RGB=3, LOCO_RGBA=4, LOCO_YV12=5};
+enum LOCO_MODE {
+    LOCO_UNKN  =  0,
+    LOCO_CYUY2 = -1,
+    LOCO_CRGB  = -2,
+    LOCO_CRGBA = -3,
+    LOCO_CYV12 = -4,
+    LOCO_YUY2  =  1,
+    LOCO_UYVY  =  2,
+    LOCO_RGB   =  3,
+    LOCO_RGBA  =  4,
+    LOCO_YV12  =  5,
+};
 
-typedef struct LOCOContext{
+typedef struct LOCOContext {
     AVCodecContext *avctx;
     AVFrame pic;
     int lossy;
     int mode;
 } LOCOContext;
 
-typedef struct RICEContext{
+typedef struct RICEContext {
     GetBitContext gb;
     int save, run, run2; /* internal rice decoder state */
     int sum, count; /* sum and count for getting rice parameter */
     int lossy;
-}RICEContext;
+} RICEContext;
 
 static int loco_get_rice_param(RICEContext *r)
 {
     int cnt = 0;
     int val = r->count;
 
-    while(r->sum > val && cnt < 9) {
+    while (r->sum > val && cnt < 9) {
         val <<= 1;
         cnt++;
     }
@@ -65,8 +75,8 @@ static inline void loco_update_rice_param(RICEContext *r, int val)
     r->sum += val;
     r->count++;
 
-    if(r->count == 16) {
-        r->sum >>= 1;
+    if (r->count == 16) {
+        r->sum   >>= 1;
         r->count >>= 1;
     }
 }
@@ -80,19 +90,18 @@ static inline int loco_get_rice(RICEContext *r)
         return 0;
     }
     v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
-    loco_update_rice_param(r, (v+1)>>1);
+    loco_update_rice_param(r, (v + 1) >> 1);
     if (!v) {
         if (r->save >= 0) {
             r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
-            if(r->run > 1)
+            if (r->run > 1)
                 r->save += r->run + 1;
             else
                 r->save -= 3;
-        }
-        else
+        } else
             r->run2++;
     } else {
-        v = ((v>>1) + r->lossy) ^ -(v&1);
+        v = ((v >> 1) + r->lossy) ^ -(v & 1);
         if (r->run2 > 0) {
             if (r->run2 > 2)
                 r->save += r->run2;
@@ -128,16 +137,16 @@ static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int heigh
         return -1;
 
     init_get_bits(&rc.gb, buf, buf_size*8);
-    rc.save = 0;
-    rc.run = 0;
-    rc.run2 = 0;
+    rc.save  = 0;
+    rc.run   = 0;
+    rc.run2  = 0;
     rc.lossy = l->lossy;
 
-    rc.sum = 8;
+    rc.sum   = 8;
     rc.count = 1;
 
     /* restore top left pixel */
-    val = loco_get_rice(&rc);
+    val     = loco_get_rice(&rc);
     data[0] = 128 + val;
     /* restore top line */
     for (i = 1; i < width; i++) {
@@ -164,13 +173,13 @@ static int decode_frame(AVCodecContext *avctx,
                         void *data, int *got_frame,
                         AVPacket *avpkt)
 {
-    const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
     LOCOContext * const l = avctx->priv_data;
-    AVFrame * const p = &l->pic;
+    const uint8_t *buf    = avpkt->data;
+    int buf_size          = avpkt->size;
+    AVFrame * const p     = &l->pic;
     int decoded, ret;
 
-    if(p->data[0])
+    if (p->data[0])
         avctx->release_buffer(avctx, p);
 
     p->reference = 0;
@@ -237,7 +246,8 @@ stop:
     return buf_size < 0 ? -1 : avpkt->size - buf_size;
 }
 
-static av_cold int decode_init(AVCodecContext *avctx){
+static av_cold int decode_init(AVCodecContext *avctx)
+{
     LOCOContext * const l = avctx->priv_data;
     int version;
 
@@ -248,7 +258,7 @@ static av_cold int decode_init(AVCodecContext *avctx){
         return AVERROR_INVALIDDATA;
     }
     version = AV_RL32(avctx->extradata);
-    switch(version) {
+    switch (version) {
     case 1:
         l->lossy = 0;
         break;
@@ -261,24 +271,29 @@ static av_cold int decode_init(AVCodecContext *avctx){
     }
 
     l->mode = AV_RL32(avctx->extradata + 4);
-    switch(l->mode) {
-    case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
+    switch (l->mode) {
+    case LOCO_CYUY2:
+    case LOCO_YUY2:
+    case LOCO_UYVY:
         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
         break;
-    case LOCO_CRGB: case LOCO_RGB:
+    case LOCO_CRGB:
+    case LOCO_RGB:
         avctx->pix_fmt = AV_PIX_FMT_BGR24;
         break;
-    case LOCO_CYV12: case LOCO_YV12:
+    case LOCO_CYV12:
+    case LOCO_YV12:
         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
         break;
-    case LOCO_CRGBA: case LOCO_RGBA:
+    case LOCO_CRGBA:
+    case LOCO_RGBA:
         avctx->pix_fmt = AV_PIX_FMT_RGB32;
         break;
     default:
         av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
         return AVERROR_INVALIDDATA;
     }
-    if(avctx->debug & FF_DEBUG_PICT_INFO)
+    if (avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
 
     avcodec_get_frame_defaults(&l->pic);
@@ -286,7 +301,8 @@ static av_cold int decode_init(AVCodecContext *avctx){
     return 0;
 }
 
-static av_cold int decode_end(AVCodecContext *avctx){
+static av_cold int decode_end(AVCodecContext *avctx)
+{
     LOCOContext * const l = avctx->priv_data;
     AVFrame *pic = &l->pic;
 
diff --git a/libavcodec/truemotion2.c b/libavcodec/truemotion2.c
index 5ba2cf10e7d7d6c23bfd7472c841e52a204dca31..82e4ec2c9cea6165dd6535a4ecb53560766bac55 100644
--- a/libavcodec/truemotion2.c
+++ b/libavcodec/truemotion2.c
@@ -93,9 +93,10 @@ typedef struct TM2Huff{
 
 static int tm2_read_tree(TM2Context *ctx, uint32_t prefix, int length, TM2Huff *huff)
 {
+    int ret;
     if(length > huff->max_bits) {
         av_log(ctx->avctx, AV_LOG_ERROR, "Tree exceeded its given depth (%i)\n", huff->max_bits);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
 
     if(!get_bits1(&ctx->gb)) { /* literal */
@@ -104,7 +105,7 @@ static int tm2_read_tree(TM2Context *ctx, uint32_t prefix, int length, TM2Huff *
         }
         if(huff->num >= huff->max_num) {
             av_log(ctx->avctx, AV_LOG_DEBUG, "Too many literals\n");
-            return -1;
+            return AVERROR_INVALIDDATA;
         }
         huff->nums[huff->num] = get_bits_long(&ctx->gb, huff->val_bits);
         huff->bits[huff->num] = prefix;
@@ -112,10 +113,10 @@ static int tm2_read_tree(TM2Context *ctx, uint32_t prefix, int length, TM2Huff *
         huff->num++;
         return 0;
     } else { /* non-terminal node */
-        if(tm2_read_tree(ctx, prefix << 1, length + 1, huff) == -1)
-            return -1;
-        if(tm2_read_tree(ctx, (prefix << 1) | 1, length + 1, huff) == -1)
-            return -1;
+        if ((ret = tm2_read_tree(ctx, prefix << 1, length + 1, huff)) < 0)
+            return ret;
+        if ((ret = tm2_read_tree(ctx, (prefix << 1) | 1, length + 1, huff)) < 0)
+            return ret;
     }
     return 0;
 }
@@ -136,11 +137,11 @@ static int tm2_build_huff_table(TM2Context *ctx, TM2Codes *code)
        (huff.max_bits < 0) || (huff.max_bits > 25)) {
         av_log(ctx->avctx, AV_LOG_ERROR, "Incorrect tree parameters - literal length: %i, max code length: %i\n",
                huff.val_bits, huff.max_bits);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
     if((huff.nodes <= 0) || (huff.nodes > 0x10000)) {
         av_log(ctx->avctx, AV_LOG_ERROR, "Incorrect number of Huffman tree nodes: %i\n", huff.nodes);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
     /* one-node tree */
     if(huff.max_bits == 0)
@@ -152,28 +153,24 @@ static int tm2_build_huff_table(TM2Context *ctx, TM2Codes *code)
     huff.bits = av_mallocz(huff.max_num * sizeof(uint32_t));
     huff.lens = av_mallocz(huff.max_num * sizeof(int));
 
-    if(tm2_read_tree(ctx, 0, 0, &huff) == -1)
-        res = -1;
+    res = tm2_read_tree(ctx, 0, 0, &huff);
 
-    if(huff.num != huff.max_num) {
+    if (huff.num != huff.max_num) {
         av_log(ctx->avctx, AV_LOG_ERROR, "Got less codes than expected: %i of %i\n",
                huff.num, huff.max_num);
-        res = -1;
+        res = AVERROR_INVALIDDATA;
     }
 
     /* convert codes to vlc_table */
-    if(res != -1) {
+    if(res >= 0) {
         int i;
 
         res = init_vlc(&code->vlc, huff.max_bits, huff.max_num,
                     huff.lens, sizeof(int), sizeof(int),
                     huff.bits, sizeof(uint32_t), sizeof(uint32_t), 0);
-        if(res < 0) {
+        if(res < 0)
             av_log(ctx->avctx, AV_LOG_ERROR, "Cannot build VLC table\n");
-            res = -1;
-        } else
-            res = 0;
-        if(res != -1) {
+        else {
             code->bits = huff.max_bits;
             code->length = huff.max_num;
             code->recode = av_malloc(code->length * sizeof(int));
@@ -233,7 +230,7 @@ static int tm2_read_deltas(TM2Context *ctx, int stream_id) {
 
     if((d < 1) || (d > TM2_DELTAS) || (mb < 1) || (mb > 32)) {
         av_log(ctx->avctx, AV_LOG_ERROR, "Incorrect delta table: %i deltas x %i bits\n", d, mb);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
 
     for(i = 0; i < d; i++) {
@@ -251,7 +248,7 @@ static int tm2_read_deltas(TM2Context *ctx, int stream_id) {
 
 static int tm2_read_stream(TM2Context *ctx, const uint8_t *buf, int stream_id, int buf_size)
 {
-    int i;
+    int i, ret;
     int skip = 0;
     int len, toks, pos;
     TM2Codes codes;
@@ -286,8 +283,8 @@ static int tm2_read_stream(TM2Context *ctx, const uint8_t *buf, int stream_id, i
             if (skip <= pos)
                 return AVERROR_INVALIDDATA;
             init_get_bits(&ctx->gb, buf + pos, (skip - pos) * 8);
-            if(tm2_read_deltas(ctx, stream_id) == -1)
-                return AVERROR_INVALIDDATA;
+            if ((ret = tm2_read_deltas(ctx, stream_id)) < 0)
+                return ret;
             bytestream2_skip(&gb, ((get_bits_count(&ctx->gb) + 31) >> 5) << 2);
         }
     }
@@ -303,8 +300,8 @@ static int tm2_read_stream(TM2Context *ctx, const uint8_t *buf, int stream_id, i
     if (skip <= pos)
         return AVERROR_INVALIDDATA;
     init_get_bits(&ctx->gb, buf + pos, (skip - pos) * 8);
-    if(tm2_build_huff_table(ctx, &codes) == -1)
-        return AVERROR_INVALIDDATA;
+    if ((ret = tm2_build_huff_table(ctx, &codes)) < 0)
+        return ret;
     bytestream2_skip(&gb, ((get_bits_count(&ctx->gb) + 31) >> 5) << 2);
 
     toks >>= 1;
@@ -720,7 +717,7 @@ static int tm2_decode_blocks(TM2Context *ctx, AVFrame *p)
 
     if (ctx->tok_lens[TM2_TYPE]<bw*bh){
         av_log(ctx->avctx,AV_LOG_ERROR,"Got %i tokens for %i blocks\n",ctx->tok_lens[TM2_TYPE],bw*bh);
-        return -1;
+        return AVERROR_INVALIDDATA;
     }
 
     memset(ctx->last, 0, 4 * bw * sizeof(int));
@@ -845,7 +842,7 @@ static int decode_frame(AVCodecContext *avctx,
     }
     p->reference = 3;
     p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
-    if((ret = avctx->reget_buffer(avctx, p)) < 0){
+    if ((ret = avctx->reget_buffer(avctx, p)) < 0) {
         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
         return ret;
     }
@@ -888,7 +885,7 @@ static av_cold int decode_init(AVCodecContext *avctx){
 
     if((avctx->width & 3) || (avctx->height & 3)){
         av_log(avctx, AV_LOG_ERROR, "Width and height must be multiple of 4\n");
-        return AVERROR_INVALIDDATA;
+        return AVERROR(EINVAL);
     }
 
     l->avctx = avctx;
diff --git a/libavcodec/tscc.c b/libavcodec/tscc.c
index 2aca0ba3b002084e10ff63dedf2570236c332fa5..7c2d2319bb19162ae1e7fbe9cc0057294e5081e4 100644
--- a/libavcodec/tscc.c
+++ b/libavcodec/tscc.c
@@ -44,10 +44,6 @@
 
 #include <zlib.h>
 
-
-/*
- * Decoder context
- */
 typedef struct TsccContext {
 
     AVCodecContext *avctx;
@@ -66,11 +62,6 @@ typedef struct TsccContext {
     uint32_t pal[256];
 } CamtasiaContext;
 
-/*
- *
- * Decode a frame
- *
- */
 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
                         AVPacket *avpkt)
 {
@@ -83,7 +74,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
 
     c->pic.reference = 3;
     c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
-    if((ret = avctx->reget_buffer(avctx, &c->pic)) < 0){
+    if ((ret = avctx->reget_buffer(avctx, &c->pic)) < 0) {
         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
         return ret;
     }
@@ -91,7 +82,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
     zret = inflateReset(&c->zstream);
     if (zret != Z_OK) {
         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
-        return AVERROR(EINVAL);
+        return AVERROR_UNKNOWN;
     }
     c->zstream.next_in = (uint8_t*)encoded;
     c->zstream.avail_in = len;
@@ -101,7 +92,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
     // Z_DATA_ERROR means empty picture
     if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
-        return AVERROR(EINVAL);
+        return AVERROR_UNKNOWN;
     }
 
 
@@ -129,13 +120,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
     return buf_size;
 }
 
-
-
-/*
- *
- * Init tscc decoder
- *
- */
 static av_cold int decode_init(AVCodecContext *avctx)
 {
     CamtasiaContext * const c = avctx->priv_data;
@@ -176,19 +160,12 @@ static av_cold int decode_init(AVCodecContext *avctx)
     zret = inflateInit(&c->zstream);
     if (zret != Z_OK) {
         av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
-        return AVERROR(ENOMEM);
+        return AVERROR_UNKNOWN;
     }
 
     return 0;
 }
 
-
-
-/*
- *
- * Uninit tscc decoder
- *
- */
 static av_cold int decode_end(AVCodecContext *avctx)
 {
     CamtasiaContext * const c = avctx->priv_data;